This feature has been described as a hengiform monument (originally by the Ordnance Survey) and a ring cairn (which is used to describe the site in the RCAHMW Brecknock Inventory). The field evidence is less clear as to the origins and purpose of this monument however. It essentially appears to be an earthwork site, the overall dimensions of which are c.12.5m x 12.5m. It is characterised by a low earth bank, grassed-over and no more than 0.3m high by up to 2m wide at base. The outer bank encloses a hollow, the centre of which is occupied by an earthwork mound. This measures c.5m x 5m at its base, 0.3m high. There is a metre wide ditch between the mound and the outer bank. When visited in January 2009, it was observed that there was virtually no stone visible on or around the site. It also appeared to be somewhat rectilinear in plan. Both of these observations may cast doubt on its identification as a ring cairn. The function and date of this site cannot easily be determined from surface evidence, although similarities with the Tir yr Onnen Barrow at Ystradfellte (Brecknock Inventory RC107, p.93) are striking and may point to this being a prehistoric funerary or ritual monument. J.J. Hall, Trysor, 9 February 2009.