Measuring roughly five metres north to south and not quite four metres east to west, and rising only about forty centimetres at its highest point, it does not announce itself as anything remarkable. It carries no ceremonial geometry, no deliberate layering, no arrangement that speaks of ritual. What it represents, according to excavation work carried out in 1993, is something altogether more prosaic: the accumulated debris of people getting on with a job.

Mooghaun is one of the largest hillforts in Ireland, a late Bronze Age enclosure whose multiple concentric ramparts enclose a considerable area on a hill above the south Clare lowlands. When builders were quarrying large stone directly from the bedrock to raise or extend those impressive earthworks, they left the spoil somewhere, and this cairn is where some of it ended up. A clearance cairn, in other words, is not a monument in the commemorative sense but a practical heap, the ancient equivalent of a builder's rubble pile pushed to the side of a working site. The limestone slabs here showed no discernible pattern in how they had been laid down. The largest, positioned at the northern end and set upright or at an acute angle, may simply reflect how they were dropped or propped rather than any deliberate design. The gravelly grey-brown soil threaded through the stones contained occasional flecks of charcoal, a small trace of human activity that the excavation noted but that resists easy interpretation. The findings were subsequently discussed by Condit and Grogan in 2005.