A leat, long disused but intended to divert water over the watershed between the high points of Gyrn and Llefn. It is approximately 300m long, 1.5m wide and 0.5m deep (max). Evidently a part of a very extensive and sophisticated pattern of water diversion in the area, the aim of which was to concentrate water resources from both the Fryddlas and the Caseg to the settlements of Rachub and Bethesda. 430m above O.D.

John Latham RCAHMW 26 April 2013