At Riverstown in County Wexford, what was once a rath, a type of circular earthen enclosure used as a farmstead or defended homestead during the early medieval period, survives not as an earthwork you can walk around, but as a ghostly cropmark, detectable only from the air. Aerial photography has revealed the outline of a circular enclosure roughly 35 metres in diameter, its presence betrayed by the differential growth of crops over buried soil disturbance beneath. Stand in the field itself and there is nothing to see; the pasture gives nothing away.

The enclosure sits on a gentle rise in an otherwise fairly level, undulating landscape, the kind of modest elevation that early farmers consistently favoured for settlement, offering drainage and a degree of visibility over surrounding ground. A field bank running roughly north-northeast to south-southwest clips the eastern edge of the enclosure, truncating it slightly, which suggests the boundary was laid down at some point after the rath had already fallen out of use and its earthworks had disappeared. This partial overlap of later agricultural boundaries on earlier archaeological features is common across Ireland, where centuries of land division have quietly dismantled and overwritten what came before.