It sits only about 0.6 metres above the surrounding fields, low enough to be dismissed as a natural rise, yet its scale gives it away: the overall diameter runs to roughly 58 metres. What makes it particularly curious is a hollow that traces the inner edge of the platform on the south-west, south-east, and north-east sides, a concentric depression that follows the monument's own margin like a shadow. Nobody has fully accounted for it.

The enclosure was described in 1944 by O'Kelly as a circular earthen platform enclosed by a fosse, which is a defensive or boundary ditch, with that unexplained concentric hollow near the platform's edge. O'Kelly's best guess was that it represented an attempt to dig away the monument at some point, though that reading is tentative at best. A later assessment by Doody in 2008 refined the picture somewhat, describing the feature as an oval ditched enclosure measuring approximately 50 metres by 42 metres, with a significant internal bank still surviving. Doody also noted that the shape and construction of the earthwork is consistent with Bronze Age enclosures, placing its possible origins somewhere in a period stretching from roughly 2500 to 500 BC, though no excavation has confirmed a date.

The site sits in low-lying, wet ground, so the approach on foot is likely to be soft underfoot, particularly in the wetter months. The enclosure is subtle from ground level, and the slight elevation of the platform over the surrounding field is easier to read from a distance than from directly on top of it. The concentric hollow that so puzzled O'Kelly is reportedly visible around three sides; looking for the relationship between the outer fosse, the raised platform, and that inner depression is probably the most rewarding thing to do once you are there. Access to sites like this in agricultural land typically requires consideration of ground conditions and any relevant permissions.