This is a bullaun stone, a type of ancient rock with one or more rounded depressions carved or worn into it, found widely across early medieval Ireland and often associated with sacred sites. The basin here measures roughly 33 centimetres by 28 centimetres and is 30 centimetres deep, hollowed into a boulder that stands a metre high and stretches nearly 1.8 metres at its widest point. What makes the spot particularly striking is the density of early Christian features clustered around it: a second bullaun stone lies only 12 metres to the east, a holy well sits 19 metres to the north, and the ruins of a medieval church stand about 52 metres to the south.

All of these features are bound together by the figure of St Fiachra, who according to tradition founded a church at Ullard in the latter part of the sixth century, a period when monastic communities were being established across Ireland by individual saints whose names then attached to the places they hallowed. The church and holy well are both dedicated to him. The association between bullaun stones and early ecclesiastical sites is well documented across Ireland, though the precise function of the basins remains a matter of debate; suggestions range from liturgical use to more practical purposes such as grinding. When the site was visited in 1994, the boulder was partially shaded by two hawthorn trees, but these are no longer there, leaving the stone more exposed on its open hillside slope.