The evidence emerged almost by accident, in May 1989, when drainage work connected with land reclamation cut through the ground and opened a trench that revealed something far older beneath the grass.

Jerry O'Sullivan of University College Cork, investigating the exposed trench sides, recorded stake holes, large pits, and charcoal lenses, the last being thin, dark layers of burnt organic material that typically indicate sustained human activity over time. These features extended roughly 48 metres to the north and about 14 metres to the south of a nearby souterrain, an underground stone-lined passage of the kind commonly associated with early medieval settlement in Ireland, often used for storage or refuge. The spread of this occupation, combined with the townland name Kilmore, which derives from the Irish for "great church", and the proximity of a burial ground some 55 metres to the east-south-east, pointed collectively toward an early ecclesiastical site. That burial ground is known locally as Cill Ronáin, St Ronan's church, a dedication that carries its own suggestion of early Christian activity in the area, though the precise date and character of any original foundation remain unclear. The northern limit of the buried features was marked by what O'Sullivan described as one large deep feature, its nature unexcavated and still unknown.