Columbia subject headings:
Harvard subject headings:
Fortification--Russia (Federation)--Novgorodskai︠a︡ oblastʹ.
Novgorodskai︠a︡ oblastʹ (Russia)--Antiquities.
Russia (Federation)--Antiquities.
Princeton subject headings:
Excavations (Archaeology)--Soviet Union, Northwestern.
Fortification--Soviet Union, Northwestern--History.
Soviet Union, Northwestern--Antiquities.