What makes it odd is precisely that it does not behave like its surroundings. Turf cutting in the vicinity has revealed that the local peat is at most half a metre deep before the mountain's original scree is reached. The mound, however, rises to two metres at its centre and stretches twenty-three metres in length, with a width of thirteen metres. When surveyors probed the upper surface with a ranging rod, they found no stone beneath the first few centimetres of sod, which rules out the most obvious explanation of a field clearance or collapsed structure. The mound tapers slightly at both ends, giving it the profile, when viewed from the side, of an overturned boat.

Surveyed by Michael Connolly as part of a study of the Lee Valley area in 1996 and 1997, the mound is oriented roughly north-north-east to south-south-west. What caught Connolly's attention was that this alignment appears to point directly between the two cairns sitting on the summit of Knockawaddra to the south-west. Mountain-top cairns of this kind are a common feature of the Irish upland landscape, typically Bronze Age in origin and used to mark high points or significant places in the terrain. Whether the mound at Skahanagh was deliberately positioned in relation to those cairns, or whether the apparent alignment is coincidental, remains an open question. What the survey established clearly is that the mound is an anomaly: too large and too regular to be a natural accumulation of peat or debris, yet without the stony core one might expect from a burial monument or a field boundary. It sits there, grass-covered and unexcavated, its origins and purpose unresolved.