This one in Castletown, on the floodplains of the Black River in north Tipperary, announces nothing at all. The enclosure that once stood here is gone, levelled to the point where there is no longer anything to see at ground level. What survives is essentially its absence, a place defined by what has been erased.

The likely cause is routine agricultural improvement. At some point, a field boundary that cut across the site was removed during land clearance, and the enclosure, probably already low-lying and unimposing on the flat river plain, appears to have gone with it. Enclosures of this kind, roughly circular or oval earthworks that once defined farmsteads or settlement areas in early medieval Ireland, were always vulnerable to exactly this kind of gradual attrition. They were rarely dramatic enough to protect themselves, and on productive lowland ground the pressure to consolidate fields and drain pasture was persistent over centuries. A companion enclosure site lies a short distance to the north, which at least confirms this was not an isolated feature in the landscape but part of a broader pattern of early activity along the Black River corridor.