Columbia subject headings:
Architecture, Medieval--Italy--Genoa.
City walls--Italy--Genoa.
Doorways--Italy--Genoa.
Fortification--Italy--Genoa.
Genoa (Italy)--Buildings, structures, etc.
Harvard subject headings:
City walls--Italy--Genoa--History.
Gates--Italy--Genoa--History.
Genoa (Italy)--History.
Porta Soprana (Genoa, Italy)
Princeton subject headings:
City walls--Italy--Genoa--History.
Gates--Italy--Genoa--History.
Genoa (Italy)--History.
Porta Soprana (Genoa, Italy)