Columbia subject headings:
Archaeology, Medieval--Congresses.
Architecture, Medieval--Europe--Congresses.
Castles--Europe--History--Congresses.
Military architecture--Europe--Congresses.
Military art and science--History--Medieval, 500-1500--Congresses.
Harvard subject headings:
Archaeology, Medieval--Congresses.
Architecture, Medieval--Europe--Congresses.
Castles--Europe--History--Congresses.
Military architecture--Europe--Congresses.
Military art and science--History--Medieval, 500-1500--Congresses.
Princeton subject headings:
Archaeology, Medieval--Congresses.
Architecture, Medieval--Europe--Congresses.
Castles--Europe--History--Congresses.
Military architecture--Europe--Congresses.
Military art and science--History--Medieval, 500-1500--Congresses.