This a Norweigian horizontal Mill.
Many trowie stories are related to Mills. The most famous trowie mill story is Winyadepla from Fetlar
In the folkloric traditions of the Orkney and Shetland islands, a trow (alternatively trowe or drow) is a small, troll-like fairy creature.[1] Trows, in general, are inclined to be short of stature, ugly and both shy and mischievous in nature. Like the troll of Scandinavian legend, with which the trow shares many similarities, trows are nocturnal creatures; venturing out of their 'trowie knowes' (earthen mound dwellings) solely in the evening, they often enter households as the inhabitants sleep. Trows traditionally have a fondness for music, and folktales tell of their habit of kidnapping musicians or luring them to their dens.
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