Columbia subject headings:
Castles--Italy--Lombardy--History.
Lombardy (Italy)--Description and travel.
Visconti family.
Harvard subject headings:
Castles--Italy--Lombardy--History.
Fortification--Italy--Lombardy--History.
Lombardy (Italy)--History--To 1535.
Milan (Italy)--History--To 1535.
Visconti family.
Princeton subject headings:
Castles--Italy--Lombardy--History.
Duchies--Italy--Milan--History.
Fortification--Italy--Lombardy--History.
Lombardy (Italy)--History, Military.
Lombardy (Italy)--History--To 1535.
Milan (Italy)--History, Military.
Milan (Italy)--History--To 1535.
Milan (Italy)--Politics and government--To 1535.
Nobility--Italy--Milan--History.