It is modest almost to the point of invisibility: a circular cairn just 2.6 metres across and 1.25 metres high, built from medium-sized stones stacked into a neat pyramidal profile. Easy to mistake for a natural outcrop, easy to walk past. What makes it quietly interesting is that it was placed here not to commemorate the dead or to mark a summit, but to settle an administrative question about where exactly one territorial division stopped and another started.

Barnies, in Irish administrative history, were large territorial units used for taxation and local governance, and their boundaries often ran across open upland where no walls or hedges could serve as markers. A cairn like this one did the job instead. What is curious about the Glenlara example is its absence from the earliest detailed mapping of the area. When the Ordnance Survey produced its six-inch maps in 1840 to 1841, this cairn did not appear. By the 1920 edition, it is there, sitting squarely on the barony boundary line and labelled with admirable plainness as "Pile of Stones". Whether it was newly built sometime between those two surveys, or simply overlooked by the earlier cartographers, the maps do not say. A second boundary cairn of the same type stands roughly 177 metres to the south-east, suggesting that this stretch of ridge was marked at intervals, the stones serving as a sparse but legible sentence written across the hillside.