This one in Ballygunneen, County Galway, earns it through almost complete absence. A small rectangular enclosure, roughly 22 metres by 18 metres, appeared on the 1921 edition of the Ordnance Survey six-inch map and has not been reliably located on the ground since. No earthwork, no wall line, no crop mark visible to a passing eye. Whatever was once here has been absorbed entirely into the surrounding pastureland.

The enclosure was modest in scale, and the most likely interpretation is that it functioned as an animal pen rather than anything more elaborate. Rectangular enclosures of this kind were common features of the agricultural landscape across Ireland, used to contain livestock and sometimes associated with seasonal or transhumance farming practices. The 1921 OS mapping, part of a revision series that attempted to record field boundaries and minor features in considerable detail, caught this one at what may have been its final legible moment. By the time anyone thought to look more carefully, the surface trace had gone.