The castle is part of a fortified architectural complex erected atop a limestone outcrop on the left bank of the Vistula River, at an altitude of 228 metres above sea level. The complex consists of numerous buildings of great historical and national importance, including the Wawel Cathedral where Polish monarchs were crowned and buried. Some of Wawel's oldest stone buildings can be traced back to 970 AD, in addition to the earliest examples of Romanesque and Gothic architecture in Poland. The current castle was built in the 14th-century, and expanded over the next hundreds of years. In 1978 Wawel was declared the first World Heritage Site as part of the Historic Centre of Kraków.