A large cairn, thought to be a clearance feature, lying within a cleared and enclosed piece of ground on the south side of Nant Tarthwynni. It measures c.10m wide east-west x 8m and is up to 1m high. It is similar to NPRNs 246608 and 246609 on the opposite side of the valley. Vegetation around the clearance cairn was grass and reeds in July 2008. J.J. Hall, Trysor, 21 October 2008.