A large oval enclosure, roughly 95 metres north to south and 140 metres east to west, is almost entirely invisible to someone walking the land. It survives instead as a shadow site and cropmark, those terms used by archaeologists to describe the way buried ditches and earthworks betray themselves from the air, either through differences in soil moisture that affect crop growth, or through subtle variations in light and shadow. A 1998 aerial photograph taken by J. Monk caught the enclosure as a slight rise and a low scarp, barely registering on the surface. A modern field boundary, running on the north-south axis, gives the game away in a different fashion: it kinks, almost apologetically, where it crosses the line of the old enclosure wall, as if something just below the surface nudged the fence-line off course.

Inside this outer enclosure, a smaller subcircular feature roughly 35 metres in diameter is also detectable from the air, part of it preserved in the curve of the existing graveyard boundary. The graveyard itself occupies what would have been the south-east quadrant of this inner enclosure, and the medieval church of Kilmaclenine sits within the larger oval, set off-centre towards the south. This layering of enclosure within enclosure is characteristic of early Irish monastic sites, where a principal ecclesiastical area was often ringed by a fosse, a defensive ditch, and set within a wider outer boundary that may have included farmland, craft areas, or the cells of monks. According to the scholars Gwynn and Hadcock, writing in 1988, the site was probably founded by St Colman mac Leinin of Cloyne, who died in 606 according to the Annals of Inisfallen. Hurley, writing in 1979, independently identified it as an early ecclesiastical site. The saint's name is embedded in the placename itself, Kilmaclenine deriving from the Irish for the church of the son of Lenine, Colman's epithet.