This one in Raheenduff, County Wexford, does none of that. It exists, to all practical purposes, only from the air. Walk across the harvested cereal field where it lies and you would have no idea you were passing through it. Look down from above, however, and the ghost of a roughly subcircular enclosure becomes visible in the soil, measuring approximately 40 metres by 35 metres, its outline preserved as a cropmark traced by a single fosse, the filled-in remnant of what was once a surrounding ditch.

A fosse of this kind, a ditch dug around a homestead to define and defend a domestic space, is the characteristic feature of a rath, the Irish term for the ringforts that were the dominant settlement form across early medieval Ireland, built and occupied roughly between the fifth and twelfth centuries. Tens of thousands are recorded across the country, ranging from modest single-ditched enclosures like this one to elaborate multi-vallate structures belonging to higher-status occupants. Most surviving examples are visible as earthworks, but a significant number have been ploughed flat over the centuries, their presence detectable only through the differential growth of crops above disturbed subsoil, where buried ditches retain more moisture and produce slightly taller or darker vegetation. This cropmark at Raheenduff was first recorded on aerial photography held in the Cambridge University Collection of Aerial Photography, and has since been confirmed on Google Earth imagery from 2010. A second rath sits roughly 140 metres to the south-east, suggesting that this was once a small cluster of early medieval settlement in a landscape that now gives nothing away.