On a low hill in a field still known locally as the 'church field', two grass-covered fragments of wall foundation are all that remain of a medieval church, their angles just legible enough to suggest a structure that once measured roughly 13 metres by 11 metres. There is no trace of an enclosure around it, and no evidence of burial, which makes it an unusually bare ecclesiastical remnant, stripped of the usual markers that help situate a ruin in time and function.

The site sits to the south-east of a natural valley that runs roughly north-east to south-west across the island, a shallow depression perhaps 80 to 100 metres wide at its top, which separates the church from a nearby motte. A motte is the raised earthen mound characteristic of early Norman fortification, and the proximity of church and motte on this small island hints at a planned medieval presence, the two structures occupying their respective sides of the valley like quiet counterparts. The church was noted by the geologist John Tuomey as early as 1850, and again by O'Broin in 1921, though neither account adds much biographical detail to what can still be seen on the ground. Bannow itself has a significant place in the Norman settlement of Ireland, the bay having served as a landing point in the twelfth century, and the wider island landscape carries that layered quality of somewhere that was once more consequential than it now appears.