Mr Nash says this is the only known location of a cup-and-ring on a chambered monument in SW Wales. Prior to this, only cups have been found (seven monuments in the region are known to have rock art).
He calls it the largest of all the monuments in Wales, so it seems strange that more fieldnotes haven’t been left on TMA? Perhaps it is rather off the beaten track. The capstone is described as a huge 5m by 4.1m, and weighing more than 60 tonnes. It is adjacent to a rock outcrop and, to the north, ‘the southern extent of Mynydd Preseli is in full view’. 50m WSW is a recumbent standing stone, a not inconsiderable 2.1m long, and ‘possibly contemporary with the Garn Turne monument’ (SM97904 27307). A second stone is at SM97935 27298. The monument, standing stones, rock outcropping and a marsh area are all inter-visible.
He says the ‘cupule’ may have been based on a natural feature of the rock, but that it shows some working. The cup is 5cm in diameter, and the ring 14cm.
from:
Cup-and-ring petroglyph on the neolithic chambered burial monument of Garn Turne, Pembrokeshire, SW Wales.
George Nash
Rock Art Research 2006 v25, no.2, pp199-206.
The article has a photo of the monument and a closeup of the cup-and-ring.
Rhiannon spents hours looking for it, someone did tell me how to get there in the end on TMP, mostly I kept ending up at Cromlech Cottage! need one of those navigating machines....