It reads as a slight thickening of the ground, a ring of earth and stone barely a metre high, eight and a half metres across, and slowly subsiding back into the bog that surrounds it. Locally, it has always been known as the "caisealinn", an Irish term suggesting a small stone fort or enclosure, though what it actually represents is something considerably older.

The structure is a collapsed cairn, a type of prehistoric monument typically built from heaped stone, often over a burial or as a territorial or ceremonial marker on high ground. What makes this one worth attention is the partial survival of its revetment on the western side, the low ring of upright stones that would originally have held the cairn's outer edge in place and given it a more defined, purposeful shape. Revetments like this are the detail that separates a deliberate construction from a natural rise, and their presence here suggests the cairn was once a more substantial feature in this landscape. The fact that the local name, "caisealinn", attached itself to the site and survived into living memory points to a long continuity of awareness, even if the original meaning of the monument was lost long before anyone thought to ask.