A burnt mound is located on boggy ground in Pant Ffosyhebog - a saddle between two hills - at 405m above OD. It is arcuate in shape and measures 10.6m (north by south) by 8.2m. The 'arc' is open to the west onto a large patch of wet ground overgrown with rushes. Here it is 0.9m high but on the east only 0.4m. The mound is turf covered with some gorse growing on it. Probing indicates the mound is largely composed of small stones.
Additional source:
Glamorgan Inventory vol.I part ii, p.126 (no.585).

David Leighton, RCAHMW, 27 November 2015