This particular cairn, a heap of loose stones roughly 3.3 metres across and standing about 2.1 metres high, is a boundary cairn, meaning it was erected not to commemorate the dead but to fix a line in the landscape, to say: here one territory ends and another begins.

Boundary cairns of this kind are a practical form of ancient land-marking, piled up at prominent points where they could be seen from a distance and where the lie of the ground itself, a ridge, a spur, a summit, reinforced the sense of a division. Placing three in alignment along the top of a spur gives the boundary a legibility that a single cairn could not. Together they describe a line. Whether that line once separated grazing territories, townlands, or some older administrative or tribal division, the stones themselves do not say. What they do suggest is that whoever placed them understood that the top of a mountain, however exposed, is also a kind of document.