Districts of Cologne within city limits), while 174,87 km² (43.2 percent) lie right of the Rhine. In regard to population, Cologne is the largest city in the state of North Rhine-Westphalia and the fourth largest city in Germany. Since the city's foundation in 38 BC, Cologne grew through numerous extensions and incorporation of surrounding municipalities. Since the construction of the Medieval wall in 1180, the area of the old imperial city of Cologne has not changed for more than 600 years and was only extended over the old city walls in 1794, just short before the arrival of French troops and Cologne's incorporation
Historical Archive of the City of Cologne municipal archive and library was erected between 1894 and 1897 to a Gothic revival design by Friedrich Carl Heimann: it was inaugurated in December 1897. The new building was large enough to accommodate the archive at a time of accelerated growth when the city of Cologne was absorbing many previously independent towns and villages. During World War II the building suffered damage from bombing. However, since all records and manuscripts had been moved into secure storage from as early as September 1939, the archive did not suffer any substantial loss. Since the archive moved to its new location in 1971,