There are a number of round barrows and cairns on this hilltop. A contributor to Notes and Queries (March 5th 1870) found some folklore referring to them in Fenton’s ‘Tour through Pembrokeshire’ (1811). “In the midst of this convulsed chaos (Plumstone Mountain) are three rocking-stones, and a cromlech ; and on the top of one of the highest fragments, in an excavation on the surface, I found water, said to be always there, and probably, as this was the 22nd of July, after a long run of dry weather.”