Columbia subject headings:
Isbister Site (Scotland)
Megalithic monuments--Scotland--Orkney.
Orkney (Scotland)--Antiquities.
Tombs--Scotland--Orkney.
Harvard subject headings:
Isbister Site (Scotland)
Megalithic monuments--Scotland--Orkney.
Orkney (Scotland)--Antiquities.
Tombs--Scotland--Orkney.
Princeton subject headings:
Excavations (Archaeology)--Scotland--Orkney.
Orkney (Scotland)
Scotland--Antiquities.
Tombs--Scotland--Orkney.