Built of dressed stone and measuring roughly three metres by two and a half, it rises to just over a metre in height, and on its flat top rests a collection of rounded, water-rolled beach stones. These were not placed there for decoration. They were used for cursing.

Penitential stations were a common feature of early Irish Christian practice, functioning as fixed points within a sacred landscape where prescribed circuits of prayer, prostration, and ritual movement were performed, often as acts of penance or devotion. What makes the Killeany example unusual is the dual character recorded by the antiquarian Thomas Johnson Westropp in 1900. Alongside its penitential function, the smooth beach stones gathered on its surface served a very different purpose, one rooted in older folk belief, where turning or handling such stones while reciting a grievance or imprecation was understood to direct harm toward an enemy. The coexistence of Christian penance and this kind of stone-turning ritual at the same structure reflects the layered religious life that characterised many early Irish sacred sites. The altar stands about sixteen metres southeast of the Killeany medieval church, within the southeastern part of the enclosure and graveyard that surround it.