Carnedd Llwyd on Moel Gallt-y-Llyn.
This is a large carnedd situated near the summit of the above named mountain [...] close to a boundary wall dividing the Nantcow and Gwastad-fryn sheep-walks. It measured about forty-five feet in diameter from east to west. It was reputed to be the repository of treasure; and some years ago an old woman, goaded by nightly visions and dreams, became so impressed with this idea, that she made a vigorous attack upon it; but the wished for prize was dashed from her thirsty lips by an avenging storm of thunder and lightning, as she herself affirms. This old lady is still living, I believe. The story was told to me by one of our workmen, who was acquainted with her.
From Archaeologia Cambrensis v3 (1852).