It measures just 0.39 metres by 0.37 metres, roughly the size of a large loaf of bread, and its upper face is worn more or less level. What makes it worth pausing over is the shallow circular basin hollowed into that surface: 14 centimetres across and 5 centimetres deep, smooth and deliberately formed.

This is a bullaun stone, a type of carved granite or other hard rock found at early ecclesiastical sites across Ireland, typically featuring one or more cup-shaped depressions ground into the surface. Their precise function is debated, but they are generally associated with early Christian and pre-Christian ritual activity, and the water that collects in their basins was often considered to have curative or sacred properties. The positioning of this example is telling: set directly on a graveyard wall, at a point where the ground level shifts, it occupies the kind of liminal, in-between space that recurs again and again in the Irish landscape wherever old religious practice left a physical mark. The graveyard at Dunboyke is itself a site of some antiquity, and the bullaun's placement on its boundary suggests a long continuity of significance attached to this particular spot on the Wicklow hillside.