On the high ground above Llyn Tecwyn Uchaf, on the old road between Llandecwyn and Maentwrog in Meirionnydd, stands a stone-covered mound known as Bedd Dorti — 'Dorti's Grave'. Local tradition holds that Dorti was a 17th-century woman widely feared as a witch, always seen with a black cat on her shoulder, who was seized by her neighbours, sealed inside a cask and thrown from the rocks above the lake. The mound marks the spot where the cask came to rest.
The story
The site carries its own surviving superstition: travellers passing the mound are expected to add a white stone to the heap, on pain of dying within the year if they fail to do so. The Royal Commission on the Ancient and Historical Monuments of Wales recorded the tradition in the 20th century, noting that even by 1943 the original arrangement of stones had been disturbed by the construction of a nearby dam — yet the cairn, and the story of Dorti, survive as one of Meirionnydd's best-known pieces of witch-lore.