The Ordnance Survey mappers who passed through in 1842 did not mark it, and neither did those who returned in 1904. Whatever it is, it went unacknowledged on the official cartographic record for decades, which is itself a quietly curious fact about a structure of considerable size.

The mound is wedge-shaped in plan, tapering from a maximum width of nineteen metres down to six and a half metres, and stretches sixty metres along its long axis, which runs north-east to south-west. At its highest point it rises to just over five metres. Those are not modest proportions. A wedge shape of this kind, aligned on that axis, in a low-lying valley beside a river, raises more questions than the available evidence can currently answer. Wedge tombs, the most common megalithic tomb type in Ireland, are typically oriented with their broader, taller end facing west or south-west, and this mound shares that general alignment, though whether it is a prehistoric monument, a later earthwork, or something else entirely remains unconfirmed. The wet, low-lying ground around it adds to the ambiguity; river valleys were used for many purposes across many periods, from early agriculture to territorial boundary-marking.