Editing Kirkwall (section)

===Earth houses===
On the western edge of the town, surrounded by Hatston Industrial Estate, there is a prehistoric monument, known as the "Grain Earth House" (see [[Historic Scotland]]). It is a short, low, stone-walled passage, deep underground, leading to a small pillared chamber. This kind of earth house (or "[[souterrain]]") is characteristic of the [[Northern Isles]] (although the Grain Earth House is unusually deep below ground). It was originally connected to a surface dwelling, which has since disappeared. The purpose of these [[Iron Age]] structures remains unknown. Further west, towards Grimbister, there is a similar structure, known as [[Rennibister Earth House]].<ref>{{Historic Environment Scotland|num=SM90245|desc=Rennibister, souterrain|access-date=22 February 2019}}</ref>