Two enclosures, one oval and roughly 30 by 25 metres across, the other a smaller circle of about 10 metres in diameter sitting just to the north-east, lie on a gently south-east-facing slope and leave absolutely no impression on the ground as it appears today. They exist, for practical purposes, only from the air.

What makes them legible at all is the phenomenon of cropmarking, whereby buried ditches or banks, long since levelled, still influence the soil's moisture and nutrient content in ways that cause the vegetation above them to grow differently, revealing outlines that become visible in aerial photography. The two enclosures at Ballygriffin were identified through exactly this process, recorded in an aerial photograph that captured their ghostly geometry against the surrounding land. Enclosures of this general type, typically defined by a circular or oval boundary ditch, are among the most common archaeological features in the Irish landscape, and they span a considerable range of periods and functions, from prehistoric settlements to early medieval farmsteads. The pairing here, a larger oval form alongside a smaller satellite circle, is a recurring arrangement, though what specific activity took place within these particular boundaries remains unknown.

Because the site is entirely invisible at ground level, there is nothing to orient a visitor standing in the field. The enclosures belong, for now, to the archive of things that the landscape holds without displaying.