It appears on none of the historical 6-inch map editions, which were otherwise diligent in recording such features across the Irish landscape. And yet the site is undeniably there, if you know how to look.

A rath is an early medieval enclosure, typically circular, defined by an earthen bank and ditch and used as a farmstead or defended homestead. This particular example, roughly 35 metres in diameter, was levelled at some unknown point in the past, erasing the visible profile that might have caught a surveyor's eye. What remains at ground level is a slightly raised circular platform, its edge defined by the gentle slope of a flattened scarp that merges almost imperceptibly with the surrounding land. A fosse, the encircling ditch, still underlies the surface, and a possible external bank once ran around the outside. It was aerial imagery and Lidar, a remote sensing technology that uses laser pulses to map ground surfaces beneath vegetation, that finally brought the site into focus, with the circular outline showing clearly in both. A band of paler grass along the western arc marks where the old bank once ran, a cropmark produced by the buried difference in soil depth and composition. The site was brought to attention by Jean-Charles Caillère, who noticed what centuries of agricultural activity and cartographic omission had quietly buried.

At ground level, the raised platform is perceptible on a careful approach from the south-west, where the fall of ground to the north gives some sense of the slight elevation the site occupies. Views to the south and south-west are now partly screened by trees and farm buildings, but the open pasture setting gives the place an unassuming quality that makes the invisible geometry beneath it all the more peculiar to contemplate.