In what would appear to be true Bronze Age fashion the cairns were not sited to be seen from below..... a rather feeble modern cairn marks Y Garn’s summit to the north.... rather, it would appear, from the ridge to the south, as here. Mynydd Mawr plays consort to the left.
Image credit: Robert Gladstone
Is that a cist structure in the foreground?
As I recall I think that's just outcropping rock... sadly.