What sets it apart is its geometry: ten upright stones are spaced evenly around the perimeter of a roughly circular mound, 7.5 metres across, giving it the appearance of something carefully planned rather than casually accumulated. Radial-stone cairns of this type are a relatively uncommon variant of prehistoric funerary or ceremonial monuments in Ireland, and this one retains enough of its original arrangement to give a clear sense of deliberate design.

The most striking feature is at the northern edge, where the two tallest stones in the circuit, standing between 0.2 and 0.9 metres high across the group and set just 1.2 metres apart, create what reads unmistakably as an entrance. Whether it was a true threshold into a ritual space or simply the remnant of a more complex structure is difficult to say, but the framing effect is hard to ignore. A depression in the western quadrant holds fragments of broken stone, suggesting that the monument has seen disturbance at some point, possibly through stone robbing or earlier investigation. A more recent addition complicates the picture slightly: a modern cairn has been built within the perimeter at the southern end, a reminder that these summits continue to attract human impulses to mark and accumulate, long after the original builders are forgotten.

The setting on Mangertonbeg, part of the Mangerton mountain group in south-west Kerry, offers unobstructed views in every direction, which may well have been a factor in the site's original selection. Hilltop placement is a recurring characteristic of monuments like this, where visibility, both of the landscape and from it, seems to have mattered as much as the structure itself.