Try to visit before noon (less visitors). Only to be visited via a guided tour (15 min, max 10 visitors per hour, sign on via the museum desk, audioguide in several languages available, taking pix of its interior is forbidden).The famous "rotunda" stands on the highest point of the castle courtyard and is the oldest preserved Romanesque roundabout. By far the most valuable Interior, even beyond national borders, is hidden in the Rotunda sv. Kateřiny: murals dating back to 1134, depicting a Gallery of the Přemyslid dynasty. The rotunda is one of the many typical roundabouts from the Přemysl period 10th century, characterized by the architectural style of contemporary influences. 1134 Konrád II, Prince of Znojmo, Gave instruction to decorate the Church with, for the then Europe, very unusual murals inspired by art of the Byzantine Empire: the biblical scenes are supplemented with a unique Gallery of the Princes of Přemyslid dynasty 10th-11th century, from the first Přemysl king, the Ploughman and the plough, a series of Prague rulers, but also other rulers of Bohemia and Moravia as well as those having the same Přemyslid rights to the throne, the Act of the Přemysl State (kind of a of painted Constitution), in the Middle Vratislaus II of Bohemia (first Czech King and older brother of Konrád).