That would be unremarkable enough on its own, except that the slab is not a plain block of masonry pressed into secondary use. Its upper surface carries a series of deep, roughly rectangular slots cut deliberately into the stone, and nobody knows with any certainty what they were originally for.

The slab is modest in size, roughly square, measuring approximately 0.3 metres thick, 0.4 metres wide, and 0.4 metres in length. Railings have since been fitted at the stile, but whoever installed them managed to avoid damaging the stone, which remains intact. The graveyard itself is recorded as DU003-011003- in the national monuments register, and it sits alongside the site of the medieval church of Garristown, catalogued separately as DU003-011001-. Researchers working on the record, including Geraldine Stout, Christine Baker, and Caimin O'Brien, have suggested that the slab may once have formed part of the fabric of that medieval church, possibly serving a structural or functional role within the building before ending up repurposed at the boundary wall. What those slots held, or how they were used, remains an open question.

Garristown is a small village in north County Dublin, and the graveyard is straightforward to locate near the church site at the centre of the settlement. The stile sits in the north-east corner of the enclosing wall, and the slab is the uppermost step, so it is visible and accessible without needing to enter the graveyard itself. It is the kind of detail that rewards a slow look rather than a passing glance. The slots are deep enough to be clearly intentional rather than the result of weathering, and running a hand along them makes the puzzle of their purpose feel pleasingly immediate. The stone has survived centuries of use and reuse, carrying its original function somewhere in its geometry, not yet fully read.