Columbia subject headings:
Harvard subject headings:
Excavations (Archaeology)--Netherlands--Leiden.
Leiden (Netherlands)--Antiquities, Roman.
Leiden (Netherlands)--Buildings, structures, etc.
Leiden (Netherlands)--History.
Princeton subject headings:
Excavations (Archaeology)--Netherlands--Leiden.
Leiden (Netherlands)--Antiquities, Roman.
Leiden (Netherlands)--Buildings, structures, etc.
Leiden (Netherlands)--History.