Columbia subject headings:
Architecture, Medieval--Congresses.
Castles--Europe--History--To 1500--Congresses.
Castles--Poland--History--To 1500--Congresses.
Civilization, Medieval--Congresses.
Harvard subject headings:
Architecture, Medieval--Europe, Eastern--Congresses.
Castles--Europe, Eastern--Congresses.
Civilization, Medieval--Congresses
Europe, Eastern--Court and courtiers--Congresses.
Princeton subject headings: