The results of this study can be used as a background and essential element for elaboration of the framework/guidelines to inform urban management and decision makers from the field of urban cemeteries, on how to best integrate the natural environment and human needs, by applying the methodical approach from the concepts of UGI, ES and BCD. For this purpose, the next step will be to broaden the research including more cemeteries in the two cities, to repeat the study and to make the findings more robust, e.g., to uncover other categories of ES provided by cemeteries and identify further trends in cemetery use, by analyzing the preferences among users (local residents and touristic visitors) in terms of the perception, use practices and management of UGI. Based on this fundamental knowledge on the interrelations of ES provided by cemeteries and the identification of particular types of cemetery use practices, we could implement a more in-depth study to determine ecological and cultural properties and performance of ES of urban cemeteries for cities, in addition to exploring how these types are allocated and distributed in urban space, and if the differences within a city are more than those between studied cities. Another direction for future research can be seen in broadening the choice and sample of test sites including other cities and other religions (we had already started with one Orthodox and one Muslim cemetery in Berlin, some years ago, as a test). Using an innovative approach (multi-mixed method of cemeteries' assessment as suggested by research framework, Figure 1) can bring together academia, city governance, and civil society, aiming towards the co-production of usable knowledge in the form of a transferable framework that can guide managers through the processes of evaluating sociocultural and biophysical conditions, determining desired future conditions, and assessing how to progress from the present to desired future conditions through collaborative creation and implementation of a management plan for future cemetery use.

#### **5. Conclusions**

**Cemeteries are an important element of cultural heritage and landscape of cities, and have a specific biodiversity potential for native species and respective niches.**

	- a. sometimes do not find space in other types of UGI;
	- b. are searching for safe and silent places in dense cities, because they are significantly different from groups that use other green spaces within the city in terms of multifunctionality, and multiculturalism being a characteristic for urban cemeteries;

#### **Biocultural diversity of cemeteries of different religions (Christian, Jewish) differs considerably within one city, in addition to land cover and management.**

	- a. Highlight certain tendencies in place-making strategies based on the fact that the cemetery is an area for negotiation between different cultural, religious and individual opinions or needs;
	- b. Specify the role of cemeteries to safeguard local (native) biodiversity, act as specific niches for local ecosystems and thus a local gene pool;
	- c. Investigate different ways of using cemeteries which are already a clearly evident part of the cemeteries' daily life, to explore different activities, and to understand people's opinions about these activities;
	- d. Determine the desired future conditions of urban cemeteries, and assess how to progress from the present to the desired future conditions through collaborative creation and implementation of a management plan.

**Author Contributions:** Conceptualization, A.D., D.D. and D.H.; methodology, A.D., D.D. and D.H.; software, A.D.; validation, A.D., D.D. and D.H.; formal analysis, A.D. and D.D.; investigation, A.D. and D.D.; resources, A.D.; data curation, A.D.; writing—original draft preparation, A.D. and DD.; writing—review and editing, A.D., D.D. and D.H.; visualization, A.D. and D.D.; supervision D.H.; project administration, A.D.; funding acquisition, A.D. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Informed consent was obtained from all subjects involved in the study.

**Data Availability Statement:** The database for the questionnaire survey is synthetically discussed in the article. The sources of elaboration on the database were based on the visitors' opinions and ratings related to given case studies from the questionnaire survey during conducted field studies in cemeteries in Łód ´z and Leipzig. All visitors' opinions from the above-mentioned sources are automatically processed to detect inappropriate content during the database elaboration and conducting of statistical analyses. Hence, the greatest value to the development of the authors' database on investigated areas was the honest and objective content posted.

**Acknowledgments:** We thank Justyna Marchewka from the Department of Human Biology, Institute of Biological Sciences, Faculty of Biology and Environmental Sciences, and Cardinal Stefan Wyszynski University in Warsaw, for help in statistical analysis. The authors would like to thank the reviewers for all useful and helpful comments on our manuscript.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **Appendix A**

**Table A1.** Comparison of response rates between respondents by nationality (chi square test).

Note: Q1. What was the reason for your visit to the cemetery?; Q2. What is your opinion on management in cemeteries?; Q3. What kind of recreational uses do cemeteries provide?; Q4. Should cemeteries be part of the city's recreational inventory?; Q5. Are the cemeteries accessible to you? 1 If *p* < 0.05, the association is significant (which implies that the analyzed factor influences the phenomenon being investigated). 2 If *p* > 0.05, the association is not significant.

#### **References**

### *Article* **Baroque Gardens in Transylvania: A Historic Overview**

**Albert Fekete \* and Máté Sárospataki**

Department of Garden Art and Landscape Design, Institute of Landscape Architecture, Urban Planning and Garden Art, Hungarian University of Agriculture and Life Sciences, 2100 Gödöll˝o, Hungary<EMAIL_ADDRESS>
**\*** Correspondence<EMAIL_ADDRESS>
**Abstract:** For over more than 20 years, Transylvanian ensembles, gardens and parks have been investigated, described and analysed by a research group from Hungary, led by Albert Fekete. The goal of this study of Transylvanian ensembles is to get background information, insight for developing a strategy for landscape preservation and development in the long run that comprises the cultural and historical values and the demands from society on what to do with them in the contemporary context. The goal of the article is to give an overview of what is already known and what could be done from the viewpoint of protection, planning and design. The research methods are mixed, but are largely based on the case study approach, supplemented by experimental design, fieldwork and research by design. The conclusion is that, given the state of what is left over from these historical artefacts, restoration in the strict sense will be impossible. This will be a major challenge for landscape architecture to take into account the historical values, integrate them with new functions and use and the recent demands of improving water management, energy transition and the creation of comfort and healthy living environments for people.

**Keywords:** history of gardens; castle garden; goosefoot avenue; star-shaped garden layout; Austro-Hungarian Empire; Transylvania as part of Romania

#### **1. Introduction**

The Carpathian Mountains are not only geographically but also culturally a crucial part of Europe's history. The multi-confessional zones along the fault lines of the Orthodox– Catholic (east–west) schism of 1054 and the Protestant–Catholic (north–south) schism of 1517 meet in the Carpatho–Pannonian region [1]. Regarding its geography, the Carpathian Basin is a coherent entity, while it is one of the most characteristic transition areas in Europe in terms of its spatial structure from political, economic and religious aspects [2]. In this landscape and regional context, Hungary and its neighbouring countries are interdependent not only geographically but also historically and culturally. For centuries, Hungary has played a leading role in this coexistence. From the conquest to the present day, the history of Transylvania is linked to the history of Hungary. For centuries, it existed either as part of Hungary or as an independent principality closely linked to Hungary, and in broad cultural and historical terms it can be interpreted as the easternmost bastion of Europe. The national unity, the intertwined history and the context of the single landscape unit also make it clear that the research of Hungarian garden art can and should be carried out comprehensively, covering the entire Carpathian Basin, and that the Transylvanian gardens from the modern period can be interpreted as some of the easternmost sites of the European garden styles from the 17th century onwards. In the history of Transylvanian gardens, the 18th century Baroque gardens that followed the late Renaissance gardens were mainly developed in connection with the residences of the local aristocracy and the ecclesiastical centres of the Roman Catholic Church (bishoprics, major monasteries). Accordingly, the main goal of the present study is to focus on research of the Baroque castle gardens of the region, highlighting their most important compositional aspects. Accordingly, the research

**Citation:** Fekete, A.; Sárospataki, M. Baroque Gardens in Transylvania: A Historic Overview. *Land* **2022**, *11*, 949. https://doi.org/10.3390/ land11060949

Academic Editors: Jan K. Kazak, Katarzyna Hodor, Magdalena Wilkosz-Mamcarczyk and Panayiotis Nektarios

Received: 15 March 2022 Accepted: 13 June 2022 Published: 20 June 2022

**Publisher's Note:** MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

**Copyright:** © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

summarises, classifies and introduces the types of the Baroque gardens surveyed through specific examples, providing information on their role and significance in Hungarian and European garden art.

#### **2. Historical Background**

After the conquest (896), Hungarian history can be divided into several periods and this division is important for the historical, economic and social aspects of the region. Figure 1 shows the most important historical periods of the Kingdom of Hungary and, in this context, of Transylvania. According to this historical division, until the collapse of the Austro-Hungarian Empire the most significant and prosperous period of the kingdom was the third period (Figure 1c), which started after the Mongol Invasion of 1241, and lasted until the Battle of Mohács in 1526. During this period, the medieval Kingdom of Hungary became a regional power; its position in international policy was the most favourable possible and its internal legislative and administrative reforms reflected a fair spirit and a strong sense of justice [3–5].

**Figure 1.** Graphical representation of the major historical periods of the Kingdom of Hungary. Source: prepared by the authors.

The Battle of Mohács, which resulted in an Ottoman victory, caused a major rupture not only in the history of Eastern Europe but also in its culture and landscape history. After the Ottoman rule following the Battle of Mohács, for a hundred and fifty years Western Hungary, Upper Hungary and Transylvania became the last bastions of the spiritual and material heritage and continuity of the European Christian culture in the region.

The fourth stage of the periods shown in Figure 1 includes the "golden age" of the independent Principality of Transylvania, 1613–1683, when Transylvania, although a vassal of the Porte, was economically prosperous, strengthened and flourishing [6–9]. During this period, Transylvanian garden culture in the late Renaissance reached a high level of excellence. At least 60 important Renaissance gardens are authentically mentioned and/or described in archival sources and in some of them it is still possible to detect Renaissance monuments and garden elements of the period [10–15].

The fifth historical period is particularly significant for the present study, as the period of absolutism following the final defeat of the Rákóczi War of Independence in 1711 marked the emergence and completion of the Baroque period in Hungary and Transylvania. From 1712, the supreme governing authority of Transylvania, the administrative and the judicial body of the region was the "Gubernium", directly subordinate to the Viennese court. Under the new balance of forces, Transylvania lost its autonomy and played a strongly subordinate role in the Habsburg Empire, both economically and politically, until the Compromise of 1867. The battles with the Ottomans or the Habsburgs, the political dependency of a once prosperous and powerful Transylvania in the 17th century, the division of the Transylvanian aristocracy and the decline of economic capabilities all contribute to the fact that the 18th century can be considered one of the darkest periods in Transylvanian history [16–19].

#### **3. Materials and Methods**

#### *3.1. Timelines of Key European Garden Styles*

When examining the characteristics of Transylvanian Baroque garden art, it is not only necessary to know the geographical and spatial location of the area under study as well as its historical background, but it is also important to know the exact chronological boundaries of the subject under study: the Baroque period of garden history. This temporal definition should be done in a European context [20–31], taking into consideration the well-known baroque garden examples and studying their compositional and functional characteristics. In this aspect the gardens from Versailles (FR), Vaux le Vicomte (FR), Montalto (IT), Hampton Court (UK), Het Loo (NL), Frederiksborg (DK), Herrenhausen (D), Nymphenburg (D), Schönbrunn (AU), Peterhof (RU) represent a comprehensive and relevant European pattern.

The development of gardens is always closely linked to the historical and economic development of a country or region. The analysis of the comparative table (Figure 2) shows that, until the national tragedy of Mohács, Hungarian garden art was on a par with European gardens. However, after the Battle of Mohács, during the 150 years of Ottoman occupation, it fell back considerably, and even after the expulsion of the Ottomans it took a century and a half to catch up the cultural delay. In the 19th century it came close to the ideas of Western European garden culture, but in terms of its overall spectrum it was only after the economic boom following the Compromise that it managed to catch up with this time lag that originated from the 16th century history [32,33]. Accordingly, Fatsar links the emergence of Baroque garden art to the appearance of the goosefoot-pattern avenues and the gradual abandonment of the orthogonal layout, which occurred at the turn of the 16th and 17th centuries [34] (Table 1).

In comparison with French or German Baroque, the transition from Renaissance to Baroque in Transylvania is much longer, and the Baroque style spread here about a hundred years later in the middle and second half of the 18th century. By this time, the connection between Western civilisation and Transylvania, which led through Hungary, had opened up. With the spread of the imperial Baroque, several western European architects and sculptors employed initially in Austria were invited to Transylvania by local aristocracy and as a result Transylvanian 18th-century architecture became an integral and representative part of the Baroque art of the monarchy [35,36].

**Figure 2.** Spatial distribution of Transylvanian Baroque gardens and their relation to the pre-Baroque late-Renaissance Transylvanian garden art; the locations of the Baroque gardens marked on the map can be identified by the numbering assigned to them (B1–B50) using Table 2. Source: prepared by Albert Fekete.

**Table 1.** Comparative analysis of the periods of major garden styles between Western Europe and Transylvania. In the last column the delayed style periods are marked with dark background. Source: prepared by Albert Fekete based on [14,37–40].

#### *3.2. Research Methodology*

Unfortunately, no Transylvanian garden has survived to this day in its original design. In a few places (e.g., Bonchida/Bon¸tida, Felek/Avrig) the main Baroque compositional elements of the gardens, such as paths, earthworks, alleys, garden structures, etc., can still be seen, but most of the Transylvanian Baroque gardens have been destroyed.

The research is therefore based on archival material and a review of the literature on Transylvanian Baroque garden art. The methodology of the archival research is known. However, the archival source material on Transylvanian castle gardens is poor. Much of the material has been destroyed, and detailed research of any existing archival material may take a long time due to the lack of proper filing and accessibility of the archives.

The research methodology of Transylvanian baroque gardens was based on the principle that the sites concerned may, and therefore must, be interpreted in context with the related settlements and landscapes as the only way to understand their historic importance and current value [41–43].

For a systematic survey we established the following theoretical framework:

The goal of the historic research of primary and secondary sources found (archives, library and museum materials, map and postcard collections, thematic bibliography reviews, internet sources, etc.) is to provide a clear idea of the establishment and development of the gardens. It comprises the role the sites play in the landscape and the urban character and layout, and the landscape scale relationships that served as a basis for the establishment of the manor garden and determined the character of the surrounding landscapes to a great extent. The garden history research also deals with the architectural history of the manor house and the family history of the owners.

The site survey precisely records the actual conditions of each garden (sketches, minutes, GPS coordinates, geodetic surveys, plant inventory, digital photographs, etc.) as well as the valuable existing features that are possible to preserve, and thus it serves as a status report and a basis for comparison for conservation strategies and any future restorations. A topographic map (e.g., land registry map) provides the basis for the survey of the general conditions and valuable landscape features.

The garden analysis based on compositional principles helps to define the most important structural types of Transylvanian Baroque gardens, which can serve as a comparison basis for further garden and landscape historical research.

Regarding the literature, we must rely on the works of two of the most dedicated and well-known personalities of Transylvanian architecture and, accordingly, of Baroque garden art, József Biró and Margit B. Nagy.

József Biró examined the palace and the palace garden as a whole in numerous relevant studies [44–46]. In his main work Transylvanian Castles, published in 1943, he devotes a separate chapter to the historical aspects of castle gardens (including the Baroque estates), as well as to the description of their contemporary condition, making it an important source document [47].

Margit B. Nagy primarily researches the architectural heritage of Transylvania, but in her works [11,37,38] she also publishes and processes inventories from the 17th and 18th centuries that contain valuable references to contemporary garden elements and archival source materials presenting them.

Apart from them, several well-known writers in the professional literature and local historians also evoke some aspects of the Transylvanian Baroque garden art [48–54], however, their works are less comprehensive, mostly referring to a single site or detail, and in several cases they refer to the works of Biró or Nagy.

#### **4. Research Results**

#### *4.1. Baroque Works and Their Masters*

The masters of gardens belong to two groups. The first group is made up of the noble families, i.e., the owners of the palaces, who in many cases are directly involved in the design and transformation of parks, gardens or individual garden elements. The owners are the source of the spirit and cultural content necessary to create the genius loci, the identity of the place and to develop the residential gardens. In many places, the owners have designed the gardens according to their own ideas or have directly influenced their design, so in a sense they can be considered as designers.

The second important group of masters is that of professionals, artists and craftsmen. With the help of archival material and other secondary sources, it has been possible to identify several architects, engineers, stone masons, sculptors, gardeners, hydraulic engineers and other professionals who played an important role in the design, construction and transformation of certain Transylvanian castle gardens or their specific elements (Table 2).

**Table 2.** List of professionals and estate owners contributed to the design of the significant Baroque gardens in Transylvania. Source: prepared by Albert Fekete based on research of archives and the literature [7,12,44,54,55].

#### *4.2. Main Types of Baroque Gardens in Transylvania*

Imre Ormos describes the four main types of Baroque gardens, which are defined in the literature on garden history on the basis of the compositional relationship between garden and building [32]. However, the division of the main Baroque garden types is not so obvious. Several interpretations of the main Baroque garden types exist in the literature, which also classify the main Baroque garden types according to a plausible logic based on different classification criteria (e.g., relief, open or closed main axis, main axis perpendicular or parallel to the axis of the palace, etc.) [34,55–64].

In the course of our research on the history of gardens, we have managed to identify a total of 50 sites in Transylvania, where we can assume the presence of Baroque garden art on the basis of mention, detailed description or representation (layout, design, painting, etc.), or can clearly establish it on the basis of surviving garden fragments and garden elements. The majority of the gardens surveyed (forty-three sites) served secular representational purposes associated with the palaces of the aristocracy, while a smaller proportion of the gardens (seven sites) were ecclesiastical (ornamental gardens of religious orders) (Table 3).

**Table 3.** The list of Transylvanian Baroque gardens surveyed, classified by the type of sources used. Source: prepared by Albert Fekete based on research of archives, the literature and site visit.

As we observe in Figure 2, many of the gardens are located close to rivers, which serve not just as water supply sources but as important traffic and transportation corridors as well. The spatial distribution of the baroque gardens follows the location of estate centres, related mainly to urban environments or to main communication and service corridors (roads).

The typological analysis of the Transylvanian Baroque gardens is based on their compositional characteristics, with particular emphasis on the path system and plant composition that determine the layout of the garden. On this basis, I have classified the gardens into five main groups.

#### 4.2.1. Gardens with Goosefoot-Pattern Avenues

The goosefoot-pattern avenues are a typical element of Baroque spatial composition and garden layout. It is a combination of avenues running in the extension of the central axis of the main building and in a symmetrical 'V' shape along the axis and terminated by a prominent feature or scene. Although the goosefoot pattern of the avenues can be traced back to the front garden of the Roman Villa, Moltanto at the end of the 16th century, the exemplar of hierarchical organisation of space based on the goosefoot avenues radiating from the main axis of the palace was the gardens of Versailles, which were developed over several decades from the 1660s onwards [34].

However, the goosefoot avenue in France was used not only in Versailles but before in the gardens of Le Notre, starting with Vaux-Le-Vicomte (Richelieu Gardens, 1627). In Versailles it was taken to its maximum expression, and, above all, it was also used for the organisation of urban space.

There are also several earlier examples with radial space compositions outside of France, for instance, Il Tridente di Roma (beginning of the 16th century) or Villa Medicea di Pratolino (Bernardo Buontalenti, 1568). In fact, the radial layout as a mechanism of spatial organisation and landscape definition was used earlier in Spain: Palacio de Aranjuez y las Huertas del Picotajo (Juan bautista de Toledo, 1553). In the Baroque period, this type of layout had a much deeper meaning, as it was usually used to cover the large scales in the forest areas and surrounding territories. It was thus contrasted with the orthogonal layout associated with the palace area. In fact, above both types of layout (radial and orthogonal), a superstructure of compositional axes was superimposed in relation to the axis of the palace. This superstructure dominated the arrangement of the entire layout.

The first simplified Transylvanian version of this classical spatial structure is the Bonchida palace and garden, developed between 1748 and 1752 by Count Dénes Bánffy, which is also the most important Baroque residence in Transylvania [44]. In addition to a pheasantry, the 400-acre estate of Bonchida (Bon¸tida) also included the most typical Transylvanian Baroque goosefoot-pattern French garden.

From the western facade of the palace, located on the plain of the Small Szamos River, three radial linden alleys extended, each approximately 1000 m long. The starting point of the alleys is the bridgehead built on the main axis of the palace. In addition to the three linden alleys, a fourth shorter horse chestnut alley ran to the north, following the water channel perpendicular to the main axis of the composition [44,47] (Figure 3).

Source: compiled by Albert Fekete, based on Dávid, Gy. [49] and the First Ordnance Survey of Transylvania (1769–1773) [65].

#### 4.2.2. Gardens with Mixed (Orthogonal–Goosefoot) Layout

The most typical Transylvanian example of the layout combining elements of both the orthogonal parterres and the goosefoot-pattern walkways is the Bruckenthal Palace Gardens in Felek (Avrig, RO), which was begun to be built between 1761 and 1764 by General Adolf

von Buccow, later governor of Transylvania. After the governor's death in 1764, the estate became the property of Baron Samuel von Bruckenthal, who used it as a summer residence and began to develop the Baroque park of about 6 ha [66]. The ornamental garden, terraced and enclosed by a stone wall because of the considerable differences in levels, is essentially orthogonal in layout, but from the water feature located in the third of the main axis away from the castle, the paths no longer run transversely but five radial walkways start, dividing the southern part of the garden into regular sections (Figure 4).

**Figure 3.** Map-based analysis of the goosefoot-pattern Baroque garden in Bonchida.

4.2.3. Gardens with Orthogonal Layout

The most common layout type of Baroque garden in Transylvania is the orthogonal garden. Its prevalence is also due to its relatively simple transparent layout, similar to a Renaissance parterre garden. It consists mostly of square, or occasionally rectangular or irregular square, compartments, sometimes intersected by diagonal or oblique paths. In the composition of the orthogonal gardens, the structural hierarchy typical of the Baroque (e.g., positioning in relation to the main building, side paths subordinate to the main walk) is only rarely present.

Source: compiled by Albert Fekete based on Feyer (2006), the First Ordnance Survey of Transylvania (1769–1773) [61] and "*Mappa prima der neuen Land- und Post-Strassen von Hermanstat bis Cronstat Mappa secunda*" [67]

The subordinate Baroque composition in the hierarchy of the network of paths or the use of the hedges is clearly visible, for example, in the Baroque garden plan of Franz Anton Hillebrandt from 1783 in Nagykároly (Carei, RO) (Károlyi Castle, Figure 5b). The same Baroque gesture of spatial organisation is much more nuanced in the Baroque garden of the Jesuit monastery in Nagyvárad (Oradea, RO), where only the two ornately designed central embroidered parterres emphasise the composition (Figure 5a).

185

**Figure 5.** Source: compiled by Albert Fekete. (**a**). The Baroque garden plan of Hillebrandt from 1783 for the Károlyi Castle in Nagykároly (Carei, RO) based on "*A tervezett nagykárolyi kastély*" [68]. (**b**). The Baroque garden plan from 1773 for the Jesuit monastery in Nagyvárad (Oradea, RO) based on "*General Plan von dem gantzen Grunde den der Jesuiten Orden vormals zu Groswardein besessen hat*" [69].

The manuscript map of the Rákóczi-Bornemisza Castle in Radnót (Iernut, RO), which was the seat of the prince in the 17th century, shows two very simple orthogonally divided geometric gardens on the west and south-west sides of the castle in the early 19th century.

Neither of these gardens form a Baroque composition with the four-cornered bastion castle building of Renaissance origin.

An aerial photograph showing the current state of the castle and garden shows the outlines and layout of a garden of a similar geometry and size to the gardens on the manuscript map and the ruins of the Baroque gatehouse (Snake House) built on the main southern axis of the castle (the location of the gate is marked by a red circle).

By superimposing the manuscript map and the aerial photograph, it can be seen that the georeferencing does not support the idea that the orthogonal garden (yellow dotted rectangle) shown in the aerial photograph on the main axis connecting the castle and the gate house would have the same size and location as the old garden depicted on the manuscript map (Figure 6).

**Figure 6.** Historic analysis of the surroundings of the princely castle in Radnót (Iernut, RO).

Source: compiled by Albert Fekete based on "*Geometrischer Plan des Radnoter Dominalgrundes*" [70], based on a Google Earth image from 2021 and on own photographs.

#### 4.2.4.  The focal point of the walkways may be located both near to the castle or at a greater distance [60–64].

Instances of radial walkways located near the castle are in Nagykároly (Carei, RO; Figure 7b), Soborsin (Săvâr¸sin, RO; Figure 8) or in Alvinc (Vin¸tul de Jos, RO). Franz Rosenstingl's 1789 plan of the castle garden in Nagykároly shows a square ornamental garden fitted to the building, with a completely symmetrical layout divided into eight sections with a parterre (or radial walkway) in the middle, which is supplemented by further geometric ornamental garden sections along a garden axis parallel to the longitudinal axis of the castle. The plan shows a subtle redesign of the Baroque garden depicted in the first military survey.

**Figure 7.** Source: compiled by Albert Fekete. (**a**). Steel engraving of the Rhédey castle garden in Erd˝oszentgyörgy from 1817 [47]. (**b**). Franz Rosenstingl's 1789 plan of the castle garden in Nagykároly (Carei, RO) based on "A nagykárolyi (Szatmár m., ma Carei, RO) régi kastély, lovarda és kert, valamint a tervezett új kastély" [71].

In the case of the castle garden in Alvinc (Vin¸tul de Jos, RO), a feature of radially shaped walkways in the ornamental garden is mentioned in an inventory from 1676, that is, from the late Renaissance period in Transylvania: "*The ornamental garden was spread out beyond the moat, east of the bridge. Divided by paths in a radiating shape, the flower and vegetable compartments enclosed a gazebo built over the fishpond, which was the centre of an obviously symmetrical composition.*" [37].

A good example of the radial walkways set further away from the castle building is the garden of the Rhédey Castle in Erd˝oszentgyörgy (Sângeorgiu de Pădure, RO; Figure 7a). It is special due to its "mixed" character, which supports Anna Zádor's observation that 19th century English gardens in Transylvania "*often retained something of the previous garden design, thus showing a somewhat mixed style, adhering to the old and the traditional*" [72], as happened in many renaissance–baroque, baroque–landscape and landscape–Victorian gardens.

From the castle in Erd˝oszentgyörgy (Sângeorgiu de Pădure, RO) a staircase runs down the terraced hillside to the lower garden and at the bottom of the hill is the bosque, divided by radial walkways with a fountain in the middle shooting high water jets [47].

Source: compiled by Albert Fekete based on "Situations Plan Der Marosch Fluss Laage bey Valliemare und jenseithts/!/bey Soborsin" [73] and own photographs.

#### 4.2.5. Baroque Gardens of Local Character

We have descriptions and depictions of several gardens in Transylvania that present Baroque gardens of a specific layout. Among these, one of the most characteristic and unique is the design of the Teleki Castle Garden in Gernyeszeg (Gorne¸sti, RO), dating from the time of Count József Teleki (I) (Figure 9).

The count's fascination with gardens is well known. During his youthful travels in Western Europe, he visited the famous gardens of his time and, like all works of art, he showed a keen interest in them. Between 1759 and 1761, he travelled through Austria, Bavaria, Switzerland, the Rhineland principalities, the Netherlands and France. In Germany, he visited the gardens of Rastatt, Karlsruhe, Mannheim and Augustusburg in Brühl, and in the Netherlands he visited the castle and park of ten Bosch, among others [41].

In the 1780s he decided to undertake a major garden renovation in Gernyeszeg (Gorne¸sti, RO), and thus the plan of 1792 by the "German gardener from Abafája" was born, the design of which was inspired by motifs of local folk decoration. Despite the interesting design elements, the count was not entirely impressed by the design, considering it to be lacking the characteristic elements of the landscape gardens that were then fashionable in Europe. [74].

Following the French Baroque garden pattern, water surfaces (the aquatic element was essential in the French Baroque and was in fact a French addition when the classical gardens were imported to France) were popular elements in some of the Transylvanian Baroque castle gardens and their placement in the geometric Baroque composition also led to specific solutions. In addition to the Haller Castle Garden in Fehéregyháza (Albe¸sti, RO) and the Bethlen Castle Garden in Kerlés (Chirale¸s, RO), there are references in the case of the Thoroczkay–Rudnyánszky Castle Garden in Torockószentgyörgy (Col¸te¸sti, RO) to a large water basin, which could be used as a fish pond, giving the garden a unique character: "*The large canal pond is an old Transylvanian tradition, as the fish pond in the former ornamental garden of the Count's castle in Torockószentgyörgy, for example, is even associated with a legend*" [44].

#### **5. Discussions**

In the garden history of Transylvania, the Baroque style was almost one hundred years late in spreading compared with other parts of Europe. In terms of the number of gardens in Transylvania, the Baroque cannot be called the leading garden style in this part of the country. The number of Baroque gardens is much lower than the number of earlier Renaissance or later Landscape Gardens (Figure 10). This is a consequence of the forced political and economic dependence of Transylvania in the 18th century.

**Figure 10.** The number of Renaissance, Baroque and Landscape Gardens in Transylvania. Source: compiled by Albert Fekete.

The majority of the Baroque gardens realised in Transylvania were of modest design, reflecting the financial constraints of an economically underdeveloped part of the country. Nevertheless, many foreign masters (gardeners, sculptors, architects, painters, jacks-of-alltrades) of Austrian, German, French, Walloon, Flemish, Czech and Polish origin worked on the design and construction of Baroque gardens of the 18th century Transylvanian noble residences. Their presence proves that Transylvanian Baroque garden art, although geographically marginalised, did not exist in isolation, but was linked to the centre of ideas through its creators and designers. The owners of the estates were aware of the European examples to follow and their artistic qualities.

Somewhat more representative Baroque gardens were developed at the residences of noble families with close ties to the Viennese court and of the dignitaries in the Roman Catholic Church.

The Transylvanian Baroque garden history is mainly about ornamental gardens, although in many places various kinds of kitchen and vegetable gardens or orchards were also part of the Baroque garden. In terms of their compositional characteristics, Transylvanian Baroque ornamental gardens are largely integrated into the general European system. They followed the models, sometimes as simplified small-scale paraphrases of them, but there are also examples that have specific local characteristics (in ethnographic and topographic terms or in plant use).

Given the state of what is left over from these historical artefacts, restoration in the strict sense is almost impossible in the majority of the locations. Devastation, missing archival sources, changing ownerships and sustainability reasons make the restoration work even harder. During the investigation, the analysis and the fieldwork of the Transylvanian ensembles, we had ample contact with local stakeholders, politicians, owners, NGOs, users and other people related to the Transylvanian ensembles. The core of the problem is concentrated around two poles: one of heritage and cultural meaning, the other on the search for new functions and uses. These two are often contradictory and conflicting; they can be categorised in the polarity between development and conservation. In all landscape architectural projects this contradiction plays a role, but in the case of historical phenomena they are even more pronounced and demand special attention [41–43,75].

This will be a major challenge for landscape architecture to take into account the historical values and to integrate them with new functions and use and the recent demands of improving water management, energy transition and the creation of comfort and healthy living environments for people.

#### **6. Conclusions**

Landscape architecture is an applied science. According to the guidelines on the preparation of scientific publications in garden history, the results of our research are based on general preliminary studies of garden and landscape history, the research results and experiences of several decades, the exploration and analysis of authentic historical sources and the site surveys and assessments. The most important findings of the research are the following:

that is an integral part of a complex system developed on artistic, cultural, historical, ecological and economic bases.

In summary, it can be said that the Transylvanian Baroque garden is considered an integral part of Hungarian garden history, although its instances are of lower quality than the Hungarian and European averages. Their importance in the field of garden history is due to the fact that Transylvania is the easternmost location of the typical garden styles of early modern Europe, and the Baroque castles and gardens created in Transylvania, mainly on the model of Western Europe, represent some of the easternmost examples of 18th century European garden design.

**Author Contributions:** Conceptualisation, A.F. and M.S.; methodology, A.F.; software, M.S.; validation, A.F. and M.S.; formal analysis, A.F.; investigation, A.F. and M.S.; resources, A.F.; data curation, M.S.; writing—original draft preparation, A.F., writing—review and editing, A.F. and M.S.; visualisation, A.F.; supervision, M.S.; project administration, A.F. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding. The publication was supported by the Hungarian University of Agriculture and Life Sciences (MATE).

**Data Availability Statement:** Not applicable.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**

## *Article* **Water Dams of the Krakow Fortress: Potential of a Vanishing Heritage**

**Wojciech Korbel 1, Filip Sucho ´n 1,\* and Marta Łapuszek 2**

**Abstract:** Cultural heritage conservation is a constant process of preserving the valuable historical legacy and transferring it to future generations. The ability to adapt the matter under conservation to changing needs and environmental conditions is an essential element of this process. In this context, climate change and its consequences are a growing challenge, requiring innovative and often simultaneous efforts. This study was conducted in response to the discovery of previously unknown documents on nineteenth-century impoundment structures of the Krakow Fortress's defensive system. At present, the facilities are almost entirely ruined, yet the need to restore and preserve the memory of their culturally valuable legacy merits investigation. The conditions and requirements of the management of Krakow's changing hydrological environment became a vital component of this study. The uncovered archival documents were subjected to historical-interpretative analysis. Virtual modeling contributed to identifying the original scope of the dams' impact. Analysis of the city's spatial planning documents pointed to their contemporary potential. The entirety of the material collected aided in determining the framework in which protective measures targeting this dying heritage are currently possible. This study features a proposal for a new form of recreating the structures under investigation by assigning them a range of possible simultaneous uses. Thus, the presented research proposal is a form of concern for preserving this historical legacy and an attempt at rising to contemporary challenges posed by an intensively changing environment.

**Keywords:** water dams; Krakow fortress; climate change; environmental management; cultural heritage conservation

### **1. Introduction**

Military engineering structures have always been an essential element of cultural heritage and have had a key impact on the development of civilization. The technical means they featured by shaping defensibility often significantly affected the natural and cultural landscape of the area they protected [1].

Along with technological advancement, changing needs, and intensive urbanization, many such structures were (and still are) altered in numerous ways, and many have irreversibly disappeared [2,3].

Therefore, the issue at stake is the ability to protect this heritage, especially where its value is undeniable. Equally essential is the ability to transfer this knowledge to successive generations while understanding dynamically changing conditions and accounting for environmental changes and sustainable development [4]. It can be observed in recent years that due to climate change the frequency and magnitude of extreme climate events such as heavy rains, flooding, and drought is increasing throughout Europe (Linnerooth-Bayer, Dubel and Sendzimir, 2015) [5]. Different risk management strategies are currently enforced in Central Europe, dealing with challenges of potential resilience-building measures and protection of cultural heritage against floods or fire (Cacciotti, Kaiser, and Sardella, 2021) [6].

**Citation:** Korbel, W.; Sucho ´n, F.; Łapuszek, M. Water Dams of the Krakow Fortress: Potential of a Vanishing Heritage. *Land* **2021**, *10*, 1273. https://doi.org/10.3390/ land10111273

Academic Editors: Magdalena Wilkosz-Mamcarczyk and Jan K. Kazak

Received: 22 October 2021 Accepted: 17 November 2021 Published: 20 November 2021

**Publisher's Note:** MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

**Copyright:** © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

The concept of heritage itself has evolved. It began with UNESCO's 1962 recommendation, raising the need to protect landscapes, natural and cultural environments that form a natural, harmonious whole. In the 1972 UNESCO Convention on the Protection of Heritage, "cultural heritage" appears, encompassing monuments and sites of outstanding universal value (Vecco, 2010) [7].

There has been some critical discussion of value typologies for heritage conservation and management in light of a review of published literature on heritage values (Fredheim and Khalaf, 2016). Considering the specificity of typologies derived from a particular context, a broad framework for assessing and communicating this meaning is proposed. This approach prevents the false division and separation of heritage into cultural and natural or tangible and intangible [8].

Another nuance is that the future of heritage is also loaded with our contemporary perceptions of the past. Given the relationship between attachment to a physical place, a sense of belonging, and the resulting importance to community life, heritage places suffer if the community does not feel connected to them. This results in neglect and vandalism (Spennemann 2011) [9].

This study was based on a separate query (performed by one of the authors) of archival documents concerning the original functioning of the Krakow Fortress. This extensive and culturally valuable complex that surrounds the city of Krakow, Poland, was built in the nineteenth century on the order of Emperor Franz Joseph I and is an element of numerous academic studies [10–12].

The original investigation conducted in the years 2014–2020 focused on the linkages between the city and its fortifications [3,13], urban structure revitalization, heritage site revitalization, and the role of modern-period fortifications in urban space, which accurately aligned itself with the scope of this study.

As a result, archival photographic and cartographic documentation was collected, presenting three poorly known water damming structures that had once been an element of the fortress's defensive system. Their general location has been shown on a plan of contemporary Krakow (Figure 1).

**Figure 1.** Diagrammatic plan of the Krakow Fortress with the locations of previously unknown impoundment structures marked in dark brown, accompanied by the boundaries of defensive areas I through VIII.

This study was based on documentation that includes the historical maps of Krakow's fortification system (drawn to a scale of 1:10,000, sheets: no. 16 "Rakowice," no. 20 "Olszanica," no. 33 "Opatkowice") [14], extension plans from the First World War (drawn to a scale of 1:10,000), and unpublished archival photographs from 1915.

In the literature on the fortress, most studies have a cross-sectional and synthetic character and refer to its history as one structure. The use of water obstacles in Krakow's defensive system has not been previously investigated. Thus, the archival materials found have supplemented the knowledge resulting mainly from the war manuals and historical standards, including an Austrian instruction for engineering and sapper forces [15,16], an Austrian permanent fortifications manual [17], and a Polish field fortifications manual [18].

These materials also provided a basis for evaluating the contemporary management of the city's aquatic environment in the context of current challenges and needs, including heritage conservation. The fortification elements studied had long lost their defensive significance, and despite the hypothetical protection afforded to historical monuments, became utterly forgotten. However, it appears that they can and should find a new application under current environmental conditions, restoring the invaluable memory of their operation in the cityscape. Based on the collected archival material and recent planning documents, this study reports on an investigation of solutions that can be best suited to preserve the disappearing heritage while also serving the goals of sustainable development.

#### **2. Materials and Methods**

An archival query was performed in search of source documentation. The study was divided into stages, and began with historical-interpretative research. The use of archival materials, iconographic sources (primarily photographs), and field research demonstrated the link between the structures identified during the query with their spatial context and relevant past events.

The authors also performed a simplified military site analysis. With this tool, hidden under the acronym KOCOA (meaning Key Terrain Observation and Fields of Fire, Cover, and Concealment, Obstacles, Avenues of Approach), it is possible to read the broad background of design and construction decisions [19]. The results of this analysis are included in the illustrations of the existing condition, provided further in the text. The location of the forts, the range of fire and mutual fire support, the blind spots, the course of wire obstacles, the relief of the terrain making observation difficult, and the expected attack directions were read from staff maps. All these elements, when superimposed, showed a rather broad approach to be dangerous for the defenders in the area of the Wilga, Dłubnia, and Rudawa river valleys.

The investigation of the context included an inspection of selected sites and the collection of photographic documentation. A literature review was performed during the comparative analysis of damming structures to other Austrian fortifications across Europe. Furthermore, spatial and environmental policy documents for Krakow were analyzed, especially in their relationships with the areas under study and the role they assigned to them.

Initial virtual modeling was applied in the study. Sections of the site in the vicinity of the former dams were modeled by CAD software. Since relief and land use have changed over the centuries, contours from historical maps were used as input data. An attempt was made to present the damming result in its original state and in a form that can currently be reconstructed. The work was carried out in three stages.

#### *2.1. Analysis of Documentation Content—The Past Significance of the Structures*

During the first stage, the archival documentation was analyzed. The technical details of the damming structures were excluded from the study as a separate problem related to heritage conservation rather than landscape planning and the environmental impact of fortifications.

During the investigation, an attempt was made to estimate the area and depth of the flooding area that resulted from impoundment during the period when Krakow's fortifications had been in active use. This analysis also concerned the potential consequences of

these effects. Analytical work was based on similar studies by other teams of researchers. In the Polish literature, similar research was performed by a group of academics from Wrocław [20,21]. The subject of this study covered light fortifications erected at the turn of the twentieth century and linked with Wrocław's contemporaneous fluvial network. This research involved the modelling of historical flows and recreating the scope of flooding on the Sl ˛ ´ eza and Widawa rivers caused by impounding the water with military dams. Based on the data collected, it also became possible to build a hydraulic model of water damming by historical weirs of the Wrocław Fortress [20].

The publications presented above became an inspiration for this study, as they covered:

#### *2.2. Analysis of the Existing State and Applicable Formal and Legal Documents—Heritage in the Present Day*

The insight gathered during the first stage was confronted with the current functioning of the structures or their remains. The second stage of the study began with a site visit. The investigation also focused on the role and possible significance of the facilities under study in Krakow's applicable spatial development policy documents.

The investigation included:

#### *2.3. Synthesis of the Information Collected in the Context of the Potential for Contemporary Conservation and Use of Disappearing Cultural Heritage*

During the final stage, the information collected during the previous stages became a basis for an in-depth discussion of the contemporary potential for preserving the heritage under study against Krakow's dynamic development background. Thus, key elements of phase three were:

#### **3. Results and Discussion**

*3.1. Results of the Analysis of the Collected Documentation and Its Application Potential*

3.1.1. General Overview of the Three Artificial Dams

Nineteenth-century defensive doctrines assumed organizing most fortresses as ringtype structures, with an external ring of forwarding forts located in the foreground and an internal ring of continuous fortifications in direct proximity to the city they defended. Considerable tracts of land were used for defensive purposes and occupied by defensive structures (divided into covers, emplacements and obstacles) [22]. Construction bans were enacted around cities to leave a free field of fire and facilitate observation. Furthermore, military doctrine assumed supplementing the permanent fortification strip (forts and batteries) with field fortifications, necessary during a state of immediate threat and mobilization [17,22] (Figure 2).

**Figure 2.** Fragment of the original plans from 1915 concerning field fortifications, an obstacle course, and a water damming on Dłubnia. From the authors' private collection.

Adaptive means and actions mainly involved "clearing the foreground" which entailed clearing forests, demolishing buildings, land leveling, etc. A constant readiness to quickly destroy bridge crossings was maintained. The potential for using water bodies and waterways for local impoundment was noted, as it would flood specific areas and make them impassable. Sapper instructions [16] highlighted the potential use of wide riverbeds and other terrain fortifications as obstacles. A watercourse could be turned into an obstacle by building hydraulic structures that formed artificial wetlands, blockages (weirs), or flooding. Depending on local conditions, they were either makeshift or comprehensive structures.

In the Krakow Fortress, the first and second defensive circuits were formed by the cities of Krakow and Podgórze, respectively, separated by the Vistula River. The borders of the remaining defensive circuits included water divisions. In the north, the third circuit stretched between the Vistula and Rudawa Rivers, the fourth from the Rudawa to the Białucha, the fifth from the Białucha to the Dłubnia, and the sixth from the Dłubnia to the Vistula. In the south, the fortification ring ran from east to west, towards the Vistula and was divided by the Wilga River into two defensive circuits [23]. With defensibility in mind, at the junction of the circuits mentioned earlier (Wilga, Rudawa, and Dłubnia), hydraulic structures were designed and built in 1914, enabling the creation of artificial inundation areas parallel to the frontline. The quality and effectiveness of these obstacles were defined using "storm resistance" ratings (originally called *Sturmfreiheit* in German). The mild or heavy flooding and wetlands created with them were to become a significant terrain obstacle [16].

Design operations preceded the process of creating such obstacles. The borders of future inundation areas were delineated, and the potential associated costs were assessed. The evaluation covered the profile of a river or channel, soil characteristics, bank incline parameters, water velocities, and information about pre-existing structures (bridges, levees, sluices, etc.). The sites for the newly designed crossings were also marked in the field, while accounting for the apparent optimization of means and resources [18].

Similar operations concerned the construction of the three dams on Dłubnia, Wilga, and Rudawa.

The Dłubnia River was impounded by improvising a blockage of the clearance under a bridge, with the concrete abutments simultaneously constituting the abutments of the weir (initially named the *Dłubnia Stauanlage*). These abutments featured vertical niches visible in the figure below, used to fasten a flat barrier (Figure 3). The dam was located along a road that connected Mogiła with Krakow. The nearest known and surviving fortification is Fort 49a Dłubnia, situated around 1 km to the north.

The Wilga's waters were dammed using a particular complex of buildings and devices. Its course could be closed using the fortress's valve weir and a second levee across the river valley (originally named *Wilga Schleuße, Staudamm a.d. Wilga*). They formed an extensive hydraulic structure dedicated strictly to military needs (Figure 4). Relatively near the weir, at around 0.5 km to the west, is the surviving Fort 52a Jugowice-Łapianka.

Water impoundment in the Rudawa river valley was performed between two waterways, namely between the Rudawa and its millrace, the Młynówka. It was located around 0.5 km to the south of Fort 41a Mydlniki. The impoundment was possible by building an earthen levee across the valley along with the channel connecting both waterways (originally named *Rudawa Inundationsdamm*). The inundation channel along with an embankment between the Rudawa and Rudawa's millrace were built in an agricultural area. An archival photograph shows a fragment of the structure with the completed earthworks and the reinforcement of the levee bank using a layer of stone. The bed of the channel had a circular cross-section, typical for structures from the beginning of the twentieth century. The photograph also shows the reinforcement of the bank zone with a system of fascines, further strengthened by fences from wooden posts and wicker. From the side where attacks were to take place, a strip of obstacles from wire on barrier rods was built (Figure 5).

**Figure 3.** View of a bridge on the Dłubnia, archival photo from 1933. Note the massive concrete abutments that were also used by the weir. From the collection of the Polish National Digital Archives, signature no. 3/1/0/8/3240.

**Figure 4.** View of the damming wall of the *Wilga-Schleuße* fortress weir, seen from the side of the inundation area. Archival photograph from 1915. From the author's collection.

**Figure 5.** View of the levee and inundation channel from the side of the Rudawa millrace. Archival photograph from 1915, from the author's collection.

3.1.2. Overview of the Size and Depth of the Inundation Areas under Study

The material collected allowed for an in-depth analysis of the size of potential inundation areas. The literature (Biesiekierski, 1922) [18] points to the application of needle dams [24] with a maximum restriction level set at around 1.8 m. By analogy, this level was also assumed for the structures under analysis.

Archival maps drawn to a scale of 1:10,000 from 1899–1902 and 1914–1915 were used, as they contained a sufficient amount of information to complete the investigation. The authors determined the flood zones based on the analysis of the topographic layout of the area. The contour lines existing on the historical map were taken into account. The assumed maximum possible level of water accumulation (approx. 1.8 m) and the contour lines indicated the range of potential inundation zones.

In the case of archival maps from the end of the nineteenth and the beginning of the twentieth century, the investigation encountered obstacles in identifying permanent points (objects) that could be referenced to contemporary landmarks. In most cases, only the forts that have survived to the present day provided an anchor. The historical maps were overlaid on the existing maps of spatial development plans and the current topographic maps to identify the relation between the historical flood zones and the recent development of the analyzed areas.

Throughout the investigation concerning the Dłubnia weir, it was possible to determine the old inundation area as potentially being up to 62.2 ha (Figure 6). The inundation surrounding Fort Dłubnia from the west strengthened the designated division between the defensive districts.

**Figure 6.** Reconstruction of the Dłubnia inundation area for the state from 1915. The watercourse was blocked by an improvised blockade under a bridge clearance. The water flowing downstream (due south) spilled successively into the river valley. Markings: A. location of the levee, B. inundation area, C. wire obstacle strip; 1. Fort Dłubnia, 2. Earthwork 1/Dłubnia, 3. Fort Mistrzejowice, 4. Fort Batowice, and 5. Fort Sudół. The expected avenues of attack are marked with arrows.

As a result of the impoundment of the Wilga with a fortress levee, an inundation was produced that was confined by a railway embankment from the west and the natural terrain layout from the east (Figure 7). The estimated total area of the historical inundation is around 29.7 ha.

Fort Mydlniki and its foreground were protected using a levee that closed a historical inundation and its accompanying parallel channel. The inundation area closed off by the levee, estimated based on historical maps and calculations, was approximately 17.9 ha (Figure 8).

**Figure 7.** Reconstruction of the Wilga inundation area for the state from 1915. The watercourse was blocked by the fortress weir. The water flowing downstream (due north) spilled successively into the river valley. Markings: A. location of the levee, B. inundation area, C. wire obstacle strip; 1. Fort Borek, 2. Fort Jugowice (a.k.a. Łapianka), and 3. Fort Wróblowice. The expected avenues of attack are marked with arrows.

**Figure 8.** Reconstruction of the Rudawa inundation area for the state from 1915. A channel was made connecting the river bed with the millstream (Młynówka). The water current filled the flat area between the two flows. Markings: A. location of the levee, B. inundation area, C. wire obstacle strip; 1. Fort Bronowice Małe, 2. Fort Mydlniki, and 3. Earthwork 1/Olszanica with batteries 1/Olszanica and 2/Olszanica. The expected avenues of attack are marked with arrows.

#### *3.2. Subject of the Study in the Present Day*

#### 3.2.1. Site Inspection Results and Their Confrontation with Archival Materials

The investigation was located in the inundations in the contemporary structure of Krakow. A detailed site inspection was performed to search for any remains.

In the Dłubnia River area, due to the remodeling of the transport system, the construction of a new bridge crossing (Figure 9), and dynamic urbanization, no remains of historical hydraulic structures have survived.

**Figure 9.** Current state of preservation of the Dłubnia inundation area, 2021.

In the Wilga riverbed, one can find the remains of its weir, in the form of a broken-up concrete slab and the fragment of the northern abutment of an earthen levee. The structural elements of the levee are visible, namely, the spaces between the stone walls filled with non-reinforced concrete and large-fraction lime aggregate. The area of the levee and weir complex is currently located in direct proximity to Krakow's expressway bypass. A part of the complex abuts the roadway, while another is an overgrown area covered with wild plants (Figure 10).

**Figure 10.** Current state of preservation of the remains of the fortress weir on the Wilga River, 2021.

In the Rudawa valley, urbanization processes and development expansion did not transform the area under study to a significant degree. Yet, agriculture and melioration work erased the course of the channel and the levee. Only a meadow is now present, slowly being overgrown with high greenery (Figure 11). The area is used to a minimal degree, mostly for farming and partially for strolling through non-landscaped greenery. The only site fully developed for recreation is a footpath that abuts the millrace bed. The technical infrastructure in the area is also not without significance: it consists of two underground Ø1200 water supply collector pipes and a high-voltage overhead power line.

**Figure 11.** Current state of preservation of the Rudawa impoundment area, 2021.

3.2.2. Analysis of the Municipality's Management Policies for the Areas under Study

The investigation of spatial development and environmental protection policy documents for Krakow first focused on the Spatial Development Conditions and Directions Study [25]. The analysis also covered other, more detailed documents on this subject, i.e., local spatial development plans drafted based on said Study [26–29] and relevant sectoral documents concerning development management.

In terms of the desired spatial structure [25] (Map K1: Spatial structure—development directions and precepts) the areas under study were assigned in both the study and applicable local plans for non-landscaped greenery conservation and design. The presence of various forms of surface waters and landscaped greenery, including parks, green squares, river parks and buffer greenery was also permitted [25] (Volume III—Guidelines for Local Plans, p. 10). Furthermore, in the Rudawa River area, a land reserve (crossing a green area) was created for the construction of a road that would connect Krakow's downtown area with the Balice airport.

The study identifies a range of climate determinants, including potential threats such as "floods and inundations, draughts, cold and heat waves, mass soil movements" [25] (Volume I Development determinants, p. 74). In terms of proposed development rules and directions, all three locations were included in a landscape preservation and shaping zone, but not in the fortified landscape conservation zone [25] (Map K2: cultural environment development and protection directions and precepts). Consequently, local development plans were also found not to highlight the historical significance of the locations in question. They were all included in the wildlife system structure as elements of river parks and cross-ventilation ecological corridors [25] (Map K3: natural environment—conservation and development conditions and precepts).

Another crucial document for this analysis is the Framework Conservation and Revitalization Program for the Historical-Landscape Complex of the Krakow Fortress [30].

The declared objectives of the program are to place fortification structures and their surrounding "fortified" landscape under legal protection, which includes the provision of local spatial development plans. The program assumes the need to revitalize these structures via their adaptive reuse as public or commercial facilities. The most valuable sites should be used as museums and exhibition spaces. The others had a range of research and academic, cultural, educational, recreational, and tourism-related uses assigned to them. The program identified a need for the general accessibility of restored fortifications by regulating legal and ownership-related matters. The structures of the fortress in possession of the Krakow municipality should be combined into a uniform historical-landscape complex, in which fortress greenery is to form a part of park areas. This document is a general collection of guidelines for the protection of fortification elements but does not mention water impoundment structures.

The document titled Development and Management Directions for Green Areas in Krakow for the years 2017–2030 is another source important to this study [31].

It asserts the necessity to form sequences of green areas that would act as ecological corridors. It indicates a need to integrate the scattered greenery structure into a continuous system, namely, the linking of existing and new public green areas via pedestrian and bicycle paths and green space sequences, to improve circulation potential and develop recreation. The document assumes a need to provide at least 10 m2 of landscaped recreational green areas per citizen. It also points to a need to support the conservation of cultural landscape zones by managing existing green space and establishing new green places.

The 2030 Krakow Climate Change Adaptation Plan [32] is an especially crucial document to this investigation. It concerns the consequences of ongoing climate change that are compounded by spatial development. It points to frequent torrential rain, inundation, flooding, and long periods with high temperatures, as well as intensive expansion of development and the growing number of vehicles. These phenomena result in a decrease in biologically active areas and water assets. The document specifies necessary preventative measures, including "informational and educational actions," "organizational actions," and "engineering actions" [20] (p. 6). The document provides a detailed list of necessary forms of activity and their associated capital expenditure. The highest priority was given to countering the consequences of floods, heatwaves, and worsening air quality via the development of broadly understood blue and green infrastructure.

The 2020–2030 Environment Protection Program Draft for the City of Krakow [33] is the last major document. Until September 2021, it had not been completed, yet its draft included crucial proposals for regulation intended to shape a socially acceptable city development strategy focused on environmental protection. In parallel, the program should facilitate socio-economic development. It includes a range of long-term goals, including the protection of Krakow's wildlife and landscape assets, increasing the share of green areas, a rational water and waste management policy, improvements to air quality, a minimization of flood risk, and ecological education for residents. The draft comprehensively corresponds with the subject of the city's spatial development and references other development strategy documents.

### *3.3. Analysis of the Collected Documentation in the Context of Modern Needs and Possibilities of Protecting the Heritage under Investigation*

#### 3.3.1. Analysis Conclusions

The analysis of archival materials presented in this study and their comparison with contemporary development strategy documents for Krakow indicated a need to take parallel action. The primary measures to be featured in these actions include:

a. The need for greater protection of the Krakow Fortress complex, including measures intended to conserve and restore the memory of buildings which are the most endangered and at risk of being forgotten.

This is the most obvious need, tied to raising public awareness about Krakow's cultural identity. The materials present new elements of Krakow's fortifications that were not previously covered by development plan provisions. The need for their greater protection nevertheless has a basis in the city's general development strategies. It is also reflected in the Polish Act on Monument Protection and Preservation [34].

b. The need to develop the city's green spaces to strengthen recreational and educational functions.

In this context, establishing a waterfront park system is an excellent opportunity to create valuable leisure spaces that would be in a state of symbiosis with the river. The necessary directions of action highlighted in the strategy documents examined are confirmed in the literature. The cases of London, Toronto, or New York demonstrate how establishing waterfront park systems facilitates ecological education and even the promotion of the city [35].

c. The need to find and design small-scale water retention sites in the spatial management system with the intent to make better use of dwindling water assets and limit the risk of local inundation.

The intensive urbanization observed over the past decades, in the absence of an effective planning system, increased Krakow's vulnerability to floods. Creating waterabsorbing areas is therefore a priority that is extensively noted in the city's development strategies. Furthermore, these measures should account for the proper distribution of retention areas and thus improve their effectiveness [36], reduce the intensity of water surges [37,38], and enhance biodiversity in floodplains [39,40].

d. The need to use and create a reserve of undeveloped land for creating cross-ventilation corridors, especially along waterways.

River valleys are areas of intensive air circulation. Ensuring they are corridors free from development is thus a priority for the correct cross ventilation of the city. This need is highlighted both in the analyzed strategy document and in many academic studies [41].

e. The need for integrated action.

Listed last, the need for integrated action deserves a special mention. This integration, often articulated in the analyzed strategy documents, supports parallel action intended to diversify the funding of advanced and costly projects. This direction finds extensive application in numerous European and global means of formulating local development policies [42,43]. The literature highlights the significance of ensuring the spatial continuity of systems, which enhances recreational potential, improves the quality of the natural environment, and the effectiveness of valley retention [44,45]. It also points to cases of comprehensive attempts at solving hydrotechnical problems, matters of shaping landscape composition and creating recreational spaces for the city [46,47] in the form of "green chains" abutting rivers.

3.3.2. Proposal of Development Action for the Subject of the Study

The need for integration listed above resulted in an analysis of possible reconstructive action in the three spaces under study. The analysis covered possible forms of action, including the capacity to form new impoundments, their potential location under contemporary conditions, possible size, and significance.

Impoundment of the Dłubnia:

The confrontation of the original inundation area with the current land development showed that contemporary recreation of the historical state is not possible. A renewed attempt at impoundment would negatively affect the structure of a roadway embankment and would reduce the safety of Okulickiego Street, which runs to its south. However, such action is partially in alignment with the city's policy, in the form of a waterfront park that would stretch along the bed of the Dłubnia, covering undeveloped space. This is an area with a length of around 500 m and a width that ranges between 80 and 230 m, occupying an area of 10.8 ha. This area could become the site of a so-called rain garden with a system of scattered, small reservoirs (ponds) which would infiltrate stormwater directly into the soil. An example of the possible layout of such ponds shall be presented in a reconstruction displayed in Figure 12. It was assumed that their combined area would not exceed half of the available site. By increasing small-scale water retention, this

concept would provide a leisure space, develop biodiversity, and protect the surrounding space. This proposal should be supplemented by a properly developed information and education system (including historical photographs and a mockup of a reconstruction of the damming structure), which would propagate knowledge about the no-longer-existing fortress's elements.

**Figure 12.** Proposal of a new inundation zone (as a part of a waterfront park) of the Dłubnia River. Markings: A. original location of the impoundment weir, B. border of the historical inundation area; 1. Fort Dłubnia, and 2. Fort Mistrzejowice.

Impoundment of the Wilga:

The historical inundation area of the Wilga River determined in this study was also found to be impossible to recreate. The original impoundment significantly extends beyond present-day undeveloped areas. Photographic documentation allows for the precise determination of the architectural form and dimensions of the sluice itself. One possible action is to rebuild it and delineate a small inundation area that would be safe for the present-day surroundings, occupying around 3.8 ha. This proposal would be a reference to the historical impoundment, creating attractive conditions for recreation, including fishing. The inundation area could be supplemented by a waterfront park, located along the left bank of the Wilga and the highway, namely, at the site in which a larger inundation area would potentially threaten the road's structural integrity. Such a park would occupy around 4.9 ha of land, and no more than half of the space would consist of water reservoirs laid out in a "chain" pattern (Figure 13). The recreated sluice, with displays showcasing its history, would be the main element of the complex, in compliance with the provisions of the Fortress Revitalization Program. Encompassing the nearby Borek, Jugowice and Wróblowice forts, all restored in 2021, the resultant complex would be highly valuable in terms of education and recreation.

The Rudawa River inundation area:

The former inundation area of the Rudawa is currently difficult to recreate. The primary hindrance here is underground municipal infrastructure that perpendicularly crosses the area, thereby limiting potential interventions. The land reserve stipulated in the area's local spatial development plan, intended for road construction, is an obstacle here. Another difficulty is the inability to precisely identify the channel's location. There are no clear traces of its presence in the area, and the applicable land development plan does not feature an obligation to reconstruct it. Despite this, the need for non-landscaped greenery which predominates in planning guidelines, can be used as a pretext for the location of a new hydrotechnical structure, and the channel identified in this study appears to be the most attractive element for reconstruction. Placed as it had been originally, perpendicular to the bed of the Rudawa, it would act as a retention reservoir that would allow water infiltration into the soil, with the possibility of draining its excess into the river [48]. The estimated area of the channel, delimited by the reserve of the planned road, is proposed to

be around 0.3 ha. The channel would be primarily an earthen structure, linked with nearby transport and circulation routes, especially pedestrian ones. It would also be an excellent example for implementing similar solutions used for periodical retention in contemporary development. Analogously to other sites, it would require proper infrastructure and annotation, providing historical knowledge (Figure 14).

**Figure 13.** Proposal for a new inundation zone for the Wilga River. Markings: A. location of the weir and levee, B. border of the historical inundation area; 1. Fort Jugowice (a.k.a. Łapianka, currently a Scout Movement Museum).

**Figure 14.** Proposal of an infiltration channel for the Rudawa River. Markings: A. location of the historical levee and irrigation channel—proposed site for the channel and infiltration reservoir, B. border of the historical inundation area; 1. Fort Bronowice Małe, and 2. Fort Mydlniki.

As a part of the investigation, an attempt was made to determine the effectiveness of the proposals presented by simulating their operation based on area estimates (Table 1).

The analysis covered the infiltration potential of the proposed solutions, as defined in three working models, while noting that the infiltration would be performed by the proposed reservoirs. The effectiveness of the total operation of the reservoirs in the waterfront parks of the Dłubnia and the Wilga was calculated, assuming maximum use. Analogous calculations were performed for the Rudawa channel. The total area of the reservoirs was set at a level of 40% of the area of the accompanying waterfront park. Each reservoir (pond) would receive surface runoff, retain it, and allow it to be absorbed into the soil. Any excess runoff would be redirected to the adjacent river [49,50]. Filtration speed was assumed to have the conditions of a unidimensional set flow through the soil, either partially or fully saturated with water, as found in Darcy [47]. It was also assumed that soil humidity

increases along with depth, until the groundwater table is reached [51]. The initial groundwater level was assumed in concordance with the real-world conditions present in the areas under study [52]. The infiltration volumes for the proposed reservoir sizes, listed in m3·s−1, are presented in Figure 15.

**Table 1.** Estimation of the area size of historical and proposed inundation areas.

**Figure 15.** Infiltration volume changes for the proposed infiltration reservoirs located in the Dłubnia and the Wilga waterfront parks and the Rudawa channel.

Furthermore, assuming an average depth for the infiltration reservoirs of only 1 m, their retention capacity would amount to 3000 m3 in the case of the Rudawa, 19,700 m3 in the case of the Dłubnia, and 43,000 m3 for the Wilga. These are volumes that can retain runoff from a fifteen-minute bout of torrential rain on a fully paved surface with an area of 30.8 ha. The areas were identified from which runoff towards the receiving waters is possible in terms of their topographic configuration. The retention capacity of the adopted solutions was estimated, The literature shows that the most significant influence on the value of the runoff coefficient is the type of catchment area coverage [53,54]. Therefore, to determine the average value of the runoff coefficient, the authors analyzed the land use of these areas (impervious roofs, roadways with asphalt surface, clinker surfaces, prefabricated concrete substrates, gravel paths, green spaces, etc.).

The analysis of the effectiveness of the proposed solutions demonstrates their significant potential. The final size selection of reservoirs requires detailed hydrological, hydraulic and topographic data. However, the findings presented prove the feasibility of simultaneous actions in which retention and infiltration significantly diminish the consequences of climate change, contributing to the conservation of cultural heritage. The

authors primarily considered the risks associated with water management and extreme hydrometeorological events: heavy, violent rains, rising rivers, and periods of drought in the absence of adequate drainage and water accumulation.

#### **4. Summary & Conclusions**

The fortress structures under study, previously unknown in the literature and the city's strategic documents, presented against the background of Krakow's spatial development needs and dynamically changing climate conditions, were used to perform an in-depth analysis of their contemporary potential.

The investigation revealed potential for the protection of a dying heritage in the form of simultaneous efforts aligned with a wider spatial management and development conducive to recreation and even the promotion of the city. This protection, more directly than before, would also address climate threats and challenges, while creating the necessary blue–green infrastructure.

The investigation produced three proposals of design solutions that combine the following goals:

The findings presented in this paper are a comprehensive proposal for taking action that would restore the memory of a widely unknown and disappearing cultural heritage and lay the groundwork for the implementation of the wider policy of sustainable development. Moreover, the concept of heritage, identification as part of the history of a place and its reception by inhabitants of Krakow, appears as a future research field.

**Author Contributions:** Conceptualization, methodology: F.S., W.K., validation, M.Ł., F.S., and W.K.; formal analysis: W.K.; investigation and resources: F.S. and M.Ł.; data curation, M.Ł. and F.S.; writing—original draft preparation, M.Ł., F.S., and W.K.; writing—review and editing, W.K.; visualization, F.S.; supervision, W.K.; project administration, W.K.; funding acquisition, W.K. All authors have read and agreed to the published version of the manuscript.

**Funding:** This publication received financial support from the Polish Ministry of Science and Higher Education under subsidy for science for the FA CUT in 2021.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** The input data in this research can be found within the article or accessed freely from online sources.

**Conflicts of Interest:** The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

### **References**

**Eliza Szczerek**

Faculty of Architecture, Cracow University of Technology, 31-155 Cracow, Poland<EMAIL_ADDRESS>
**Abstract:** The paper focuses on the phenomenon of intense, uncontrolled densification of large-panel housing estates in Poland. Despite the fact that such housing estates as a legacy of the Modernist concept of segregation of functions are often burdened with problems, they still have considerable potential, which results predominantly from their urban advantages, such as functional and spatial logic, large amounts of open public space, and abundance of greenery. Unfortunately, this potential is being destroyed by introducing new buildings, ignoring the existing urban layout of the housing estate along with its original compositional assumptions. This type of densification results from without limitations—the pressure exerted by developers in the free-market economy, and it often leads to problems such as the devastation of urban layouts of these housing estates, breaking the continuity of public spaces, appropriation of green areas, strengthening of monofunctionality, etc. This problem is becoming noticeable in the scientific debate, although it is still difficult to obtain reliable data illustrating the densifications of such housing estates. The goal of this paper is to present the scales and character of such densifications of the large-panel housing estates, which pose a threat of devastation of their urban layouts often considered as urban heritage. The paper proposes a method of a quantitative analysis of the housing estates with reference to the increase in the built-up area and a qualitative analysis of the character of development with reference to its distribution. This method comprises a sequence of subsequent steps with relevant criteria. In the results, it demonstrates the scale of the problem, which in many cases is already big and still growing. The resultant threat of devastation of the urban layout and its consequences are presented upon selected examples of housing estates in Cracow, Poland. This paper is a voice in a discussion devoted to the current status, but most of all to the future of large-panel housing estates, particularly in terms of their protection as valuable achievements of urban planning of the second half of the 20th century, and to stopping unfavorable tendencies of urban destruction.

**Keywords:** urban densification; prefabricated housing estates; spatial devastation; protection of urban layout; Cracow

#### **1. Introduction**

The modernist urban thought breaking with the hitherto understanding of urbanity held in the spirit of the doctrine contained in the Athens Charter [1] changed the course and direction of the development of many cities. Years of looking for a new formula of housing contributed—among others—to the development of housing estate structures, which—in contrast to the conventional urban tissue based on the pattern of a street and a square—promoted detached apartments blocks, which were to secure optimal ventilation, insolation, and access to green areas.

The second part of the 20th century saw more and more new housing estates built in Europe. It was a period of economic and demographic development, which accompanied the reconstruction of towns and cities after the war. A crucial role in this respect was played by the industrialization of construction technologies. Advancement in prefabrication processes accelerated the process of building housing estates considerably. Their most prominent development took place in countries of Eastern Europe, where the centrally

**Citation:** Szczerek, E. The Problem of Densification of Large-Panel Housing Estates upon the Example of Cracow. *Land* **2021**, *10*, 1359. https://doi.org/ 10.3390/land10121359

Academic Editors: Jan K. Kazak, Katarzyna Hodor and Magdalena Wilkosz-Mamcarczyk

Received: 2 November 2021 Accepted: 6 December 2021 Published: 9 December 2021

**Publisher's Note:** MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

**Copyright:** © 2021 by the author. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

controlled housing market, an element of the planning strategy of the communist regime, fostered the emergence of large-panel housing estates. Cheap and effective solutions in the housing sector were promoted and implemented with great elan and on a large scale.

In Poland, housing estate structures, most commonly executed in the 1970s, have become inherent elements of landscapes of numerous towns and cities. Their scale is quite significant—in 2016, as much as 40% of urban households were situated in apartment buildings from 1956–1989, mainly in housing estates built in industrialized technologies [2]. It is estimated that in 2020, 30% of residents of Poland (ca. 12 million people) lived in large-panel blocks [3].

Prefabricated housing estates, which constitute a legacy of the modernist segregation of functions, are a difficult heritage in terms of their architecture and urban planning. They are often burdened with a number of spatial problems, such as monofunctionality, monotony of development, repetitiveness of forms, low-quality architecture of apartments buildings, amorphous and undefined spaces, or spatial degradation and isolation [4–8], as well as social ones [9–11] including stigmatization, negative image [12,13], and safety issues [14]. On top of that, there are technical problems associated with the low quality of materials used [15] and poor energy performance [16], although the latter has been dealt with to a great extent by broadly implemented insulation and window replacement projects.

More and more often, large-panel housing estates in Poland are recognized as crisis areas [17]. Nevertheless, the threat of their physical and social degradation is not as big as in similar housing estates in Western Europe, which is predominantly connected with a gap in the housing market as well as a demand for relatively inexpensive apartments [18]. Furthermore, Poland still demonstrates a considerable housing deficit of ca. 640,000 apartments [19]. In relation to the housing estates in Western Europe, it seems that the estates in post-socialist cities will undergo changes according to their own scenarios [20].

Yet, despite many negative phenomena, large-panel housing estates still have considerable potential, resulting predominantly from their urban values and public open spaces associated with them [21]. Frequently, they are characterized by a functional and spatial logic as well as abundance of green areas, which are strongly related to the residential development [22–24]. Time and again, the overall urban layout of a housing estate corresponds to local conditions, making use of such natural advantages as the lay of the land or the vicinity of valuable landscapes [8]. Thus, many of them constitute valuable testimonies to urban planning achievements of Late Modernism, which require adequate protection [3,25].

Against the background of many contemporary housing estates, large-panel housing estates create a housing environment of a better quality and constitute a favorable living environment [26,27]. In many contemporary housing estates, we have to deal with spatial and social problems [28–30]. Small distances between buildings—although still consistent with legal regulations, 'peering into windows', or fencing, the latter being a hallmark of social exclusion, are their standard elements. There is not enough park and public greenery, sports and recreation grounds, sufficient services, education, trade, etc. Consequently, more and more frequently, the contemporary multi-family architecture is referred to as 'housing pathology' [31,32].

In the context of large-panel housing estates, they may pose a particular risk due to two aspects. Firstly, individual buildings or clusters thereof sprawl within the perimeter of housing estates, appropriating valuable open space and destroying their urban composition. Secondly, in many newly erected contemporary developments with multi-family buildings located in the direct vicinity of large-panel housing estates, residents use the existing infrastructure of large-panel housing estates, comprising e.g., schools, healthcare facilities, as well as greenery, as there are no legal regulations that would impose the obligation to build such facilities, as it used to be the case before the planning system reform [29]. Thus, besides certain services in ground floors, such housing estates, oriented toward the highest profits possible generated from residential spaces, often constitute single-use formations, taking a lot from large-panel housing estates but not giving much in return.

The aforementioned excessive and chaotic densification of large-panel housing estates with new development constitutes a common and significant problem, which may lead to the gradual devastation of such housing estates [33]. It happens that new buildings are placed in the areas, which originally were designed as recreational and leisure zones for residents [34]. Since the new buildings most of all are residential ones, monofunctionality is strengthened even more. New buildings are often fenced to be separated from the remaining parts of housing estates, which additionally disturbs the continuity of public spaces of a housing estate and is unfavorable for establishing appropriate relations in the social dimension. This overlaps with the problem of an increased demand for parking spaces, which also take over the space of housing estates considerably [35–39].

The first tendencies of densification of housing estates in Poland started to emerge as early as in the 1980s. They were caused by—among other factors—policies of housing cooperatives, which recognized selling parts of their territories as more economical than maintaining them in an undeveloped state [40]. Intensification in introducing new buildings can be observed since the 1990s, which was supported by the political transformation and new free market mechanisms it entailed. This new situation coincided with rather inefficient planning mechanisms regulating the spatial development of housing estates. However, to a certain extent, they did ensure the protection of unoccupied areas allocated to the greenery of housing estates under the general masterplan from 1994 covering the entire territory of Poland. The situation changed considerably when this plan was repealed in 2003 and no new one was resolved to replace it. This results in allocating these grounds to buildings, in compliance with the law [41]. Intensified and aggressive pressure exerted by developers has far-reaching spatial consequences, which are expressed predominantly in the aforementioned densification of housing estates. It is particularly unfavorable to them, since their urban layout, composition principles, and green areas are decisive for their character and identity as well as for the way they function.

The process of forming as well as functioning of large-panel housing estates in the communist socio-economic system is generally well known and present in the scientific literature. However, the situation of their spatial change after the political transformation are still not sufficiently recognized and described. The problem of densification of largepanel housing estates is becoming noticeable in the scientific debate; however, there are still not enough sources of data referring to the problem, especially to its scale. These processes of densification intensify gradually, and they affect different housing estates to different extents. Even though noticed by urban planners as well as residents, they have yet to be analyzed and provided with comprehensive databases, which would allow developing a methodological foundation for the assessment of the existing or potential threats, as well as formal and legal solutions that could be undertaken to prevent them.

Therefore, the goal of this paper is to present scales and character of such densifications of large-panel housing estates, which pose a threat of devastation of their urban layouts often considered as urban heritage [2,3,25]. Conclusions formulated in this paper may constitute a source of information on tendencies of spatial changes happening in such housing estates as well as provide inspiration to undertake systematic measures toward the rationalization of these processes.

This paper fills a gap in the state of the art concerning the problem of the threat of devastation of the urban layouts of large-panel housing estates in Poland, which are also understood as the structures of urban heritage, caused by chaotic densification, after the introduction of a free-market economy as a result of the transformation of the political system.

The article is divided into five parts. Following the Introduction, Section 2 describes the study area—Cracow large-panel housing estates—and introduces methods comprising a sequence of subsequent steps with relevant criteria, as well as provides datasets sources. Section 3 presents the result of the quantitative analysis related to the scale of densifications as well as a qualitative analysis related to their spatial character. Additionally, an in-depth analysis of selected examples is presented to support the research findings. In Section 4, the author discusses the results in a broader context, referring to selected aspects. Section 5 concludes with a summary of the main results of this research and highlights future research directions.

#### **2. Materials and Methods**

#### *2.1. Study Area—Cracow Large-Panel Housing Estates*

The study area comprised large-panel housing estates in Cracow (Figure 1)—the main city of the Province of Małopolskie. As the second largest city of Poland, besides the local specificity characteristic for each settlement market with a specific individuality, it demonstrates many tendencies and mechanisms characteristic of big cities. Thus, it illustrates the problems that concern large-panel housing estates in other Polish cities. In addition, a significant number of prefabricated housing estates in Cracow allows for a broader study of the problem.

**Figure 1.** Arrangement of large-panel housing estates in the structure of Cracow.

The beginnings of large-panel housing estates in Cracow are associated with the need to provide a large number of apartments, most of all in connection with its constantly growing population after the war. Cracow avoided the need to rebuild its urban structure, including housing resources, as practically, it had not suffered any considerable damage during the war. Housing estates, erected over the span of three decades, were located on the northern and southern side of the city.

The early 1960s saw the emergence of—among others—housing estates in the northern part of the city, such as Azory and Olsza II, as well as housing estates associated with the extension of the metallurgical plant built in the 1950s, i.e., the Wzgórza Krzesławickie housing estate and shortly after that the first from the group of Bie ´nczyce housing estates. The late 1960s and early 1970s also marked the beginnings of the construction of such housing estates as Krowodrza, Widok, D ˛abie, and Pr ˛adnik Czerwony. The extension of the development of Nowa Huta was also continued, with a group of four Mistrzejowice housing estates erected there: Tysi ˛aclecia, Złotego Wieku, Bohaterów Wrze´snia, and Piastów [42]. At the same time, the Podwawelskie and Na Kozłówce housing estates were emerging on the southern bank of the Vistula.

The emerging new developments affected the gradual change of the spatial layout of Cracow from a bipolar to a band-shaped one. The 1970s is a period when distances between one's workplace and residence increased considerably, and the existing tramway no longer sufficed, as it was overloaded. It was a time when a network of bus connections got extended. The year 1973 saw another broadening of the city's administrative limits aimed to mitigate the deficit of construction lands [43]. The subsequent development of the city was based on a plan adopted in 1977, which had a significant impact upon the process of forming housing estates. The plan assumed two parallel bands of development coexisting together, with the historic city center as their keystone [44,45]. In addition to the housing estates whose construction had already begun in the southern band, i.e., Prokocim Nowy and Piaski Nowe, toward the end of the 1970s, the construction of the next housing estates was commenced: Biezan ˙ ów Nowy and Wola Duchacka Wschód. In the northern bank, after moving the airport from Czyzyny to Balice, the development of these areas ˙ started in 1978, with the Dywizjonu 303 housing estate built to the north from the runway and the II Pułku Lotniczego housing estate to the south from it.

In the 1980s, the construction of this housing estate was continued, but also new ones started to emerge. The Kombatantów housing estate was built in the norther band, which was followed later by the O´swiecenia housing estate. Wola Duchacka Zachód, Kurdwanów, and Ruczaj-Zaborze developments were erected in the southern band.

Sporadically, the construction of housing estates continued to the early 1990s, with the Rz ˛ ˙ aka housing estate as an example. In the ornamentation of its architectural details, it makes a reference to the aesthetics of Post Modernism, which were for the first time applied in Cracow in industrialized residential developments [29]. In the early 1990s, the construction of the Mistrzejowice Nowe housing estate was continued as well.

Housing estates built with the application of industrialized technologies are a significant element in the urban structure of Cracow in terms of territory. Housing developments from the 1960s and early 1970s constitute ca. 25% of all apartments located in the city. The highest number of apartments, ca. 35%, are located in housing estates built in the 1970s and early 1980s [44].

The greatest accumulation of housing estates is in the eastern part of the city, particularly in the northern band, where the extension of the metallurgical plant in Nowa Huta mentioned above was an important stimulus for their coming into being. Even though these housing estates were built in different times and most often are independent from each other in administrative terms, they form a vast complex of housing estates due to their often direct proximity. It has its effect on the identity of this part of the city, which to a great extent is identified with this type of architecture.

Housing estates located in the southern part of the city due to the considerable area they occupy strongly define the character of this part of Cracow as well. However, in contrast to housing estates in Nowa Huta, they do not often border on one another. A feature that can be recognized as characteristic is the fact that they appear as islands among areas of one-family houses, which divide housing estates into separate clusters. Such a situation can be observed in Wola Duchacka, which is a housing estate that is formally divided into an eastern and western part, with the latter additionally consisting of two 'islands' of large-panel buildings. Furthermore, similarly to the Cegielniana and

Na Kozłówce housing estates, the territory occupied by large-panel buildings assumes a shape resembling the letter 'U', surrounding one-family houses. In the northern part, a similar situation can be seen in the Azory housing estates, which are visibly interspersed with one-family houses.

In Cracow, many housing estates from the second half of the 20th century are recognized as areas requiring many issues to be resolved [44] and they have been covered by the 'Program of Multi-family Housing Development Rehabilitation in the Area of Cracow Municipal Commune' [46]. As in many other Polish towns and cities, currently, one of the biggest problems of Cracow is the chaotic densification of such housing estates with new buildings. The way the lands are administered is not beneficial for the spatial situation of housing estates in Cracow. Most lands, even though they are the property of the Municipality of Cracow, are lent for use to numerous entities, and consequently, there is no direct control over them, which in turn makes it harder to make any comprehensive decisions. Furthermore, due to more and more frequent cases of buying them up by different entities, this situation may worsen still [41], since—as it has been mentioned before—their densification is often chaotic, with no respect for the entire context and no well-considered, holistic approach. One of the consequences of densification of housing estates is their fragmentation, which is caused by fencing off areas and by the loss of spatial cohesion due to taking green areas over by cars.

#### *2.2. Methods*

The base for pursuing the research goal referring to the scale and the character of urban densifications of the housing estates from the second half of the 20th century is provided by the author's literature studies [8,20,33,34,38,39,47] and scientific experience in this subject matter. This paper presents a more detailed insight into threats to large-panel housing estates, basing on numerical and qualitative data, extending the knowledge in this field. It fills the gap in the existing studies focusing on this problem, particularly in the context of devastation of valuable urban layouts of such housing estates, which are recognized as heritage.

Currently, it is difficult to obtain data illustrating the problem of densification of such housing estates. Different methods are characteristic for the discipline of science: Architecture and Urban Planning have been applied in an attempt to characterize this problem upon the example of Cracow [48]. They are presented in the following steps:

• Step 1. Indication of the analyzed housing estates within the city limits (Figure 1).

Qualitative criteria: Construction technology, time and place of construction, genesis, urban compositional layout.

Comment: The analysis covers housing estates built in industrialized technologies (initially in the large-block technology and then in large-panel technologies, which were used on a large scale across European countries, especially in Eastern Europe). Therefore, for the sake of clarity and simplification of deliberations in this paper, they are predominantly referred to as large-panel housing estates. Sometimes, they are also referred to as prefabricated housing estates or estates built in industrialized technologies. Ultimately, all these phrases refer to the same kind of housing estates and are used interchangeably.

The article refers to housing estates that were built on a large scale in Cracow in the second half of the 20th century. The time adopted is connected with the political system the time of the communist rule, which had a significant impact on the process of designing such housing estates.

Such housing estates constitute a legacy of the modernist segregation of functions and urban composition, as they were built in the spirit of modernist ideas promoted by the Athens Charter [1].

• Step 2. Defining the areas of the analyzed housing estates (Figure 2).

Quantitative criterion: Housing estate's boundary.

Comment: Areas of selected housing estates were defined following Lynch's 'district' category [49], which is understood as a homogenous area with a uniform character in which one has a feeling of being inside or outside of this area.

• Step 3. Characterization of densifications of the analyzed housing estates.

Quantitative criterion: Increase in the built-up area [%] (Table 1, Figure 3). Qualitative criterion: Characteristics of the way new buildings are introduced:

Comment: The increase in the built-up area in the housing estates was defined quantitatively, comparing figures from the mid-1990s and 2021. This time cut-off point is connected with a radical transformation of the political, economic, and social system in Poland, which had a significant impact on such housing estates. The mid-1990s is a transitional period between the already collapsed centralized national economy during the communist time and a newly emerging free market system of a democratic reality. The centrally controlled housing market within the communist regime promoted the implementation of such big spatial and functional urban projects, including large-panel housing estates. With the political transformation and the free market economy, a completely new mechanism in the housing market and urban planning appeared. Even though 1989 was a breakthrough year for the social and political system in Poland, the processes associated with designing such housing estates were sometimes continued in the early 1990s. That is why 1995 was selected as a turning point in the analysis performed, where figures from the mid-1990s and 2021 were compared.

The percentage of the increase in the built-up area was determined by comparing data from a vector map obtained from the City Hall Cracow and other maps available online within the scheme of the Municipal Spatial Information System for Cracow [50] with data from satellite images from 1995.

An analysis was performed covering the densification of central areas of housing estates as well as their peripheral zones, causing disturbances of spatial edges.

• Step 4. Reference to the urban heritage structures and local spatial development plans in the context of the housing estates (Table 2).

Quantitative criterion (a): Recognition of the estates as urban heritage structures. Quantitative criterion (b): Presence of local spatial development plans:

Comment: Housing estates as urban heritage structures were indicated on the basis of the results of a research project [2]. An analysis of coverage of large-panel housing estates with local spatial development plans was performed on the basis of information available in the Public Information Bulletin of the City of Cracow [51].

• Step 5. Indication of monofunctional clusters of apartment blocks in the vicinity of large-panel housing estates. (Figures 6 and 7, Table 3).

Quantitative criterion: Presence of such clusters in areas adjacent to the large-panel housing estates.

Comment: Such complexes of monofunctional residential areas may have a negative impact on the functioning of the housing estates (described in more detail in the Introduction).

• Step 6. An in-depth description of selected examples of housing estates with a valuable urban composition (Figures 8–11).

Qualitative criterion: High spatial devastation of the urban layout of the housing estate, which is caused by intensive densification with new buildings.

Comment: This is to illustrate more vividly the threat of devastation of their urban layouts.

Results of the analyses are presented in a form of a systematic overview of changes within housing estate structures and in areas adjacent to them caused by their densification as well as diagrams illustrating this problem quantitatively.

#### **3. Results**

While analyzing spatial metamorphoses within the perimeter of large-panel housing estates in Cracow, it was noticed that their densifications assume different scales and characters and most importantly affect nearly all the housing estates. It is particularly striking in the case of urban layouts of such housing estates with high compositional values, which have been recognized as structures of urban heritage. New buildings were not observed only in one housing estate (Figure 2, Table 1).

**Table 1.** Densification values for large-panel housing estates in Cracow (%).

#### *3.1. Quantitative Characteristics of Densifications*

The quantitative analysis of the increase in built-up areas in the housing estates covered their territories, taking into account their possible extensions if their edges were shifted due to adding new buildings (situations referred to in Section 3.2 as A and B). Quantitative results are presented below (Table 1, Figure 3). The table contains values illustrating the development of the housing estates with reference to the area increased by newly erected buildings: the first column refers to buildings from before 1995, the second refers to buildings erected after 1995 to date (2021).

**Figure 2.** Map of a part of Cracow with areas of the analyzed housing estates marked (black border). 1—Widok, 2—Azory, 3—Krowodrza Górka, 4—Pr ˛adnik Biały Zachód, 5—Pr ˛adnik Biały Wschód, 6—Pr ˛adnik Czerwony, 7—Olsza II, 8—Ugorek, 9—D ˛abie, 10—O´swiecenia, 11—Tysi ˛aclecia, 12—Złotego Wieku, 13—Bohaterów Wrze´snia, 14—Piastów, 15—Mistrzejowice Nowe, 16—Kombatantów, 17—The group of Bie ´nczyckie housing estates, 18—Dywizjonu 303, 19—II Pułku Lotniczego, 20— Wzgórza Krzesławickie, 21—Podwawelskie, 22—Ruczaj-Zaborze, 23—Cegielniana, 24—Wola Duchacka Zachód, 25—Wola Duchacka Wschód, 26—Na Kozłówce, 27—Kurdwanów, 28—Piaski Nowe, 29—Prokocim, 30—Biezan ˙ ów Nowy, 31—Rz ˛ ˙aka.

**Figure 3.** Diagram illustrating a relative development increase in large-panel housing estates in Cracow.

An analysis of the increase in the built-up area demonstrates that densifying housing estates with new buildings is more intensive in the southern part of the city, and on average, it reaches 18.2%. The average increase in built-up areas in the northern housing estates is 13.8%. The total average for all the housing estates is 15.4%.

The biggest number of housing estates—14—increased their built-up area within the range of 1 to 10%. Eight housing estates were in the range 10–20%. In six housing estates, the increase is at the level of over 30%. The housing estates that stand out due to the largest increase in the built-up area, i.e., 30% or more, are Kurdwanów, Dywizjonu 303, and O´swiecenia housing estates.

One of the methods of controlled development of housing estates can be local spatial development plans. Some of the housing estates in Cracow have such plans drawn up, covering their entire perimeter or a part thereof. It was also verified whether similar plans cover adjacent areas, which might be significant particularly for the protection of green areas around the housing estates (Table 2). It was presented in the context of the information which estates are recognized as urban heritage structures [2] (Table 2).

**Table 2.** List of housing estates recognized as urban heritage structures with their entire territories or parts thereof covered with local spatial development plans.

Today, i.e., in 2021, 14 out of the 31 analyzed housing estates or their complexes (11 out of the 23 housing estates recognized as urban heritage structures) are covered with local spatial development plans, whereas seven of them have been in force since 2020. Four housing estates are not covered with overall local spatial development plans at all, and 13 housing developments are only in selected parts or on their edges.

#### *3.2. Qualitative Approach—Characteristics of Spatial Metamorphoses of the Housing Estates*

The analysis of densifications of large-panel housing estates allows defining certain trends in the way new buildings are introduced. These trends are characterized below.

A. New development is introduced as single buildings or clusters of buildings in unoccupied spaces between apartments buildings. It happens both in central areas of housing estates and in their peripheral zones (Figure 4).

**Figure 4.** Densification with single or clusters of buildings inside housing estates—selected examples: (**A**)—Pr ˛adnik Czerwony (6), (**B**)—Prokocim (29), (**C**)—Widok (1), (**D**)—Wola Duchacka Wschód (25), (**E**)—Pr ˛adnik Biały Zachód (4). Color legend: black—developments from before 1995; red densification—developments from after 1995.

B. In situations where new buildings are introduced in the peripheral zones of a housing estate, such buildings tend to push beyond its perimeter, or to push its edge outwards, to be more precise, thus pushing outwards the boundary of the housing estate, informally increasing its territory (Figure 5). It often entails taking over areas that used to constitute green areas: a buffer zone of the housing estate. In densifications of this type, one still can speak of a certain affiliation of new buildings to the structure of the housing estate, at least in terms of belonging to a certain 'district', which is understood in Lynch's categories as an area that is as homogenous as possible, in which one has a feeling of being inside or outside of this area [49]. The affiliation of new buildings to a large-panel housing estate may be also strengthened by a distinct spatial edge located behind it, e.g., a green belt, a river, or a street, particularly a major one.

C. Furthermore, there are situations where a complex of multi-family buildings has been built in the direct vicinity of a housing estate (and frequently, its construction is still in progress), with the dominating residential function and very few accompanying functions. If the scale, character of buildings, and their location toward the existing largepanel housing estate provide them with features that make them stand out, this study does not recognize them as an extension of the housing estate but as a separate structure. Nevertheless, due to the potential influence of such structures on large-panel housing estates mentioned in the introduction, they are included in this paper as the neighborhood of housing estates (Figure 6).

The nature of structural metamorphoses within housing estates and in areas adjacent to them for all the housing states in Cracow according to the tendencies described above is presented in Table 3.

**Figure 5.** Densification with single buildings or clusters of new buildings on the edges of the housing estates, shifting their boundaries (the extended area is marked with a dotted line)—selected examples of housing estates: (**A**)—Krowodrza Górka (3), (**B**)—D ˛abie (9), (**C**)—Wzgórza Krzesławickie (20), (**D**)—Podwawelskie (21). Color legend: black—developments from before 1995; red—densification developments from after 1995.

**Figure 6.** Neighborhood of clusters of multi-family buildings with the dominating residential function—examples in the context of selected housing estates: (**A**)—Ruczaj (22), (**B**)—Olsza II (7), (**C**)—Wola Duchacka Zachód—northern part (4), (**D**)—Piaski Nowe (28). Color legend: black developments from before 1995; red—densification—developments from after 1995; orange—other multi-family housing areas next to the large-panel housing estates.

**Table 3.** Characteristics of the way new buildings are introduced within the perimeter and in areas adjacent to large-panel housing estates.

> Most frequently, these situations occur simultaneously in housing estates. In addition to the already mentioned densifications within the perimeter of the housing estates, which occur nearly in all the analyzed housing estates, in 13 of them, a partial shift of their edge can be additionally observed, and seven share the neighborhood with new complexes of residential buildings. In four housing estates, all these phenomena were observed.

> Considering the types and intensity of densifications, the housing estates that demonstrate the most far-reaching spatial changes are the Dywizjonu 303 housing estate (34.2%), the O´swiecenia housing estate (30.6%), and Kurdwanów (30.0%) (Figure 7).

> In the Dywizjonu 303 and Kurdwanów housing estates, intensive densifications with single buildings and clusters thereof take place within the perimeter of the housing estates, as well as in their outskirts, in some cases shifting the original edge of the housing estate, which has changed the original valuable urban composition. Furthermore, they are accompanied with areas of intensive residential development. In the housing estates in

Czyzyny (the Dywizjonu 303 housing estate and the II Pułku Lotniczego housing estate), ˙ unoccupied areas on the southern side of the runway have been adapted for the Nowe Czyzyny housing estate. Due to certain controversies and a significant influence of this ˙ project on the housing estates in Czyzyny, this case is described in more detail ˙ in Section 3.3.

**Figure 7.** Cracow large-panel housing estates with the highest intensity of densification: (**A**)—the Dywizjonu 303 housing estate; (**B**)—the Kurdwanów housing estate; (**C**)—the O´swiecenia housing estate. Color legend: black—developments from before 1995; red—densification—developments from after 1995; orange—other multi-family housing areas next to the large-panel housing estates.

In the O´swiecenia housing estate, there are no single buildings added inside the housing estate; however, there are two distinct clusters of new buildings in the edge area. In the context of the formula of defining new buildings as belonging or not belonging to a housing estate as adopted in this paper, regarding the complex of buildings in the northern part of the housing estate as an extension of the O´swiecenia housing estate instead of an independent project may seem debatable. This is due to the fact that this part of the development is generally regarded as officially belonging to this housing estate as its extension. It is worth pointing out that the southern part of the housing estate, with a characteristic meandering structure, has maintained its urban layout and there are no new additions between apartments blocks there.

The housing estates that have no or the lowest degree of densifications, i.e., Ceglana, Kombatantów, Ugorek, Tysi ˛aclecia, and Piaski Nowe, demonstrate their original, nearly unchanged layout of the entire development. However, in the latter, a cluster of multifamily residential buildings has emerged adjacent to it, and it is still being extended.

#### *3.3. Selected Examples of Spatial Devastation*

The above considerations, presented in Sections 3.1 and 3.2, allow selecting examples in which adding new structures to large-panel housing estates recognized as urban heritage structures entails squandering of their potential by destroying their urban composition and other urban values.

The influence of this type of densifications can be considered according to the set of the following qualitative criteria, characterizing the basic aspects of the functioning of housing estates:

Ones of blatant examples in this respect are the aforementioned housing estates in Czyzyny: Dywizjonu 303 and II Pułku Lotniczego, which are located on both sides of the ˙ historic runway of the former airport Rakowice-Czyzyny (Figures ˙ 8 and 9). Aggressive measures undertaken by developers (level of densification: 34.2% and 19.2%) caused utter devastation of the post-military heritage of the area, which besides constituting a true loss in the scale of the city directly affects the adjacent large-panel housing estates. The new development is partially fenced off and almost monofunctional. This is an example of the densification process, which is aimed at private interest, not the common one, especially in the context of the neighboring large-panel housing estates [35].

**Figure 8.** Densifications of housing estates in Czyzyny in the context of destruction of their main ˙ potential—the former runway. Based on an ortophotomap (www.maps.google.com; accessed on 5 December 2021). Color legend: white area—approximate area of the former airport Rakowice-Czyzyny with a specified runaway (white stripe); black buildings—developments from before 1995 ˙ (mostly within the scheme of the construction of the housing estates in Czyzyny); red—densification— ˙ developments from after 1995.

Similarly enough, metamorphoses observed in the Bohaterów Wrze´snia housing estate and the Piastów housing estate in Mistrzejowice move toward a particularly unfavorable end. Devastating densifications (28.2% and 10.9%) take place predominantly on their northern and western outskirts, shifting and changing the character of their edges (Figures 10 and 11), which according to the original design were planned as a green buffer zone [42].

From the side of the Bohaterów Wrze´snia housing estate, the green buffer zone is provided by Planty Mistrzejowickie park, and from the north, it is provided by areas of the former defense ring of the Cracow Fortress, with still preserved structures of the former forts: Mistrzejowice and Batowice, surrounded by abundant vegetation, once fulfilling camouflage purposes. The document 'Program of the Cracow Fortress Protection Plan' [52] describes this area as worth protecting.

The problems connected with the densification process described in the examples above are associated with—inter alia—their negative influence on the urban layout of these housing estates, breaking of the continuity of their public spaces, devastation of the historical and cultural potential, strengthening of monofunctionality, and appropriation of valuable green areas. Taking over green areas by aggressive investments constitutes a serious problem. Key green areas disappear and their continuity is broken, which causes irreversible destruction of these areas. It is a significant loss not only in the context of the housing estates themselves but the entire city, too. Urban values of the housing estates have been irreversibly destroyed.