At almost 50ft in diameter, this summit cairn is well worth a shufti when checking out the nearby Cerrig Cewri....
Coflein reckons the monument is:
“An apparently undisturbed cairn, 15m in diameter and 1.6m high, having an Os triangulation pillar set upon its summit. A standing stone, Carreg craig-y-moch, 2m by 0.6m by 0.5m, once stood c.550m SSW of the cairn, reported as erect in 1967, it was prostrate by 1968 and had been removed in afforestation by 1976. [J.Wiles 04.04.02]”