Five-stone circles are a distinct prehistoric monument type found almost exclusively in south-west Ireland, characterised by their compact diameter and the presence of two portal stones flanking a recumbent axial stone. This example at Kealkill sits on a level, bog-covered shoulder of a north-west-facing slope, intact and complete, which is itself something of a rarity.

When Seán P. Ó Ríordáin excavated the circle in 1938, the results were quietly puzzling. The five stones, ranging in height from 0.65 metres to 1.2 metres, had not been deeply embedded in the ground at all; instead, they were packed at their bases with small stones, a construction technique that raises questions about how such monuments were stabilised and maintained. More intriguing were two shallow trenches found inside the circle, cutting across each other at right angles and filled with dark, humified soil. Ó Ríordáin interpreted these as the traces of crossed wooden sleepers, possibly the foundation for a central upright post that no longer survives. No artefacts were recovered from the excavation, leaving the circle's original purpose, and the meaning of that probable post, open to interpretation. The internal axis of the circle runs north-east to south-west, an alignment that appears deliberately chosen, though its precise astronomical significance remains debated. The circle does not stand in isolation; a radial stone cairn, a type of wedge-shaped burial monument, lies to the east, and a pair of standing stones stands to the north-east, suggesting that this was once a more elaborate ceremonial or funerary landscape rather than a single isolated feature.