There is nothing on the surface to suggest it is there, no earthwork, no raised ground, no scatter of stone. The only evidence of its existence came from the air, when aerial photographs taken in 1996 revealed its outline as a cropmark, the subtle discolouration in growing vegetation that betrays buried features beneath a field.

Cropmarks form when buried structures, whether ditches, walls, or pits, affect how plants grow above them. Soil over a filled-in ditch retains more moisture and nutrients, producing lusher, taller crops; compacted surfaces do the opposite. From the ground these differences are imperceptible, but from altitude the buried geometry of an earlier landscape becomes legible. The enclosure at Kiltilliha was identified by M. Moore through an aerial survey programme, and the photographs show a large circular form, the kind of outline associated with enclosed settlements of the early medieval period in Ireland, though without excavation the date and function of this particular example remain uncertain. What is notable is its complete absence from the first edition Ordnance Survey six-inch map, the mid-nineteenth-century survey that recorded countless earthworks across the country. Either the enclosure was already too degraded to be visible by that point, or the land had been reclaimed and levelled before the surveyors arrived. The site sits on flat, open ground with a stream running immediately to the west, a detail that fits patterns of settlement where fresh water was kept close at hand.