No earthwork rises above the surface, no stones mark the perimeter; the feature is visible only from the air, and only under the right conditions. When crops grow unevenly because buried archaeology disrupts soil moisture and nutrients, the past announces itself in pale or dark rings, lines, and blotches. This is what is known as a cropmark, and it is the only form in which this particular ring-ditch survives.

A ring-ditch is typically the eroded remnant of a prehistoric burial monument, most often a round barrow whose central mound has long since been ploughed away, leaving only the circular ditch that once surrounded it. The feature at Oldtown was identified by Simon Dowling using Google Earth Pro, from satellite imagery captured on 28 June 2018. That summer date is significant; cropmarks tend to appear most clearly during dry spells when vegetation stress reveals what lies beneath. The image shows not only the circular feature but also a field boundary running roughly east to west straight through it, itself visible only as a cropmark, suggesting that the boundary too is of some age, though it cuts across the earlier monument without any apparent awareness of what it was crossing. Roughly 170 metres to the south lies a possible enclosure, and about 270 metres to the southwest there is a large irregular enclosure, hinting that this corner of Kilkenny preserves, just below the ploughsoil, a cluster of features from a landscape that was once much more legible.