Columbia subject headings:
England--Antiquities.
Inclosures--England--Essex.
Iron age--England--Essex.
Woodham Walter (England)--Antiquities.
Harvard subject headings:
England--Antiquities.
Essex (England)--Antiquities.
Excavations (Archaeology)--England--Essex.
Inclosures--England--Essex.
Iron age--England--Essex.
Woodham Walter (England)--Antiquities.
Princeton subject headings:
Aerial photography in archaeology--England--Essex.
Essex (England)--Aerial photography.
Essex (England)--Antiquities.
Excavations (Archaeology)--England--Essex.