Inner Chamber, Main Cairn, Camster, Scotland The central chamber of the main cairn at Camster is round in shape and is approached through a small passageway that requires one to crawl or squat and walk through the opening section. Previous: Hüven-Nord Steingrab (Passage Grave), Niedersachsen, Germany Next: Kercado Passage Tomb, Carnac, Brittany, France