Columbia subject headings:
Castles--Europe--History.
Siege warfare--Europe--History.
Harvard subject headings:
Castles--Italy--History.
City walls--Italy--History.
Fortification--Italy--History.
Italy--History, Military.
War in art
Princeton subject headings:
Castles--Italy--History.
City walls--Italy--History.
Fortification--Italy--History.
Italy--History, Military.
War in art.