Rennibister Earth House is located on the Mainland of Orkney, in Scotland. It is located by the south eastern shore of the Bay o' Firth, in a farm yard and is accessed by a hatch in the roof of the earth house and by a ladder. The souterrain was discovered when a threshing machine caused the roof to collapse on 12 November 1926 and seems to date from c. 1000 BC. Access was originally by a passage that was low, with a small drop into the chamber. The chamber itself has 4 pillars supporting the roof, and 5 alcoves in the walls. Unusually, the chamber had the remains of 6 adults and 12 children.