At Ardeenloun in County Waterford, there is almost nothing left to see, and that absence is precisely what makes the place worth knowing about. On a gentle slope facing south-east, a set of field boundaries that were old enough to be mapped by the Ordnance Survey in 1840 managed to persist, at least as faint earthwork traces, for well over a century before finally disappearing from the landscape altogether.

The boundaries appear on the first edition of the OS six-inch map, the great mid-nineteenth-century survey that recorded Ireland's rural landscape in extraordinary detail, capturing field patterns, townland edges, and agricultural divisions that in many cases stretched back centuries. At Ardeenloun, some of those marked boundaries survived as relict features, meaning they were no longer functioning field divisions but had left enough of a physical impression in the ground to remain legible. Aerial photographs taken in the 1970s still caught them, the kind of low-angle light or crop variation that makes buried or eroded earthworks briefly visible from the air. By the time those images were examined and recorded, however, the features themselves had gone.