The hillfort was reoccupied in the 2nd and 3rd centuries and then by the Slavs in the 9th century, at the time of the Great Moravian Empire. The Slavic settlement at Kostolc was preceded by the settlement at Pobedim. It was destroyed in the 1st half of the 9th century, probably as a result of the expansion of Prince Mojmir in the territory of today’s Slovakia in the years 830-833. The hillfort at Kostolc was settled around 850, it was in the form of a great manor with an area of approximately 0.5 ha. For its defence, an older rampart and a Bronze Age moat were used. A wooden palisade was built on top of the rampart. A stone rotunda with an apse stood inside the hillfort.

The courtyard disappeared sometime in the middle of the 10th century. The rotunda a little later. From the end of the 10th century to the 14th century, the surroundings of the rotunda served as a cemetery. It is estimated that up to 1900 people were buried here during this time. Around the middle of the 15th century the hillfort served as a Hussite military camp. Burials were made here again in the modern period from the last third of the 16th century to the second third of the 19th century. There are approximately 340-360 burials.

Source: www.hrady.cz