Despite carrying the name of a church in its record, no church building and no graveyard have ever been identified here. What survives instead is something stranger and more ambiguous: a large enclosure running roughly east to west, marked on the 1909 Ordnance Survey six-inch map in the italic lettering conventionally used for antiquities, and labelled, with some romance, the 'Friars Garden'. Its boundary is a collapsed rubble bank, best preserved at the eastern end where it still stands between half a metre and a metre high. Iron slag found on the northern shore in the 1940s adds a further, unexplained industrial note to what otherwise reads as an ecclesiastical site.

The island's patron is recorded as St Colum or Cainneach of Inishkeen, and scholarship has raised the possibility that this figure may be the same person as St Cainneach of Kilkenny and Aghaboe, one of the more prominent Irish saints of the sixth century. Whether or not that identification holds, the physical traces of early Christian activity on the island are real, if modest. Towards the eastern end of the Friars Garden enclosure, set into a small stone cairn roughly five metres by three, there is a cross-slab, a thin upright stone with an incised cross cut into its eastern face. Nearby sits a D-shaped cut-stone base, moulded around its edge, that once supported some form of pillar. A second cross-slab from the island, a trapezoidal sandstone piece bearing two nested equal-armed crosses with forked and T-bar terminals and concentric circles around the crossing point, was removed and is now held in the National Museum of Ireland. Together these fragments suggest a site of early medieval religious significance, even as the absence of any identifiable church structure leaves its precise character open.