A large circular enclosure in the townland of Ballybroman, in north County Kerry, falls squarely into this category. A rath, or ringfort, is a roughly circular earthwork enclosure, typically dating from the early medieval period and used as a defended farmstead. This one was large enough to be mapped twice by the Ordnance Survey, once in 1841 to 1842 and again in 1898, yet nothing of it remains visible on the ground today.

The site lies in the field immediately south of a neighbouring enclosure, the two once forming a close pair in what would have been a farmed and settled landscape. Early medieval ringforts are found in their thousands across Ireland, but their survival is far from guaranteed. Agricultural improvement, drainage work, and the gradual levelling of earthworks over generations have erased many entirely, leaving only the paper record behind. In this case, the Ordnance Survey maps provide the only evidence that something substantial once stood here, large enough that nineteenth-century surveyors considered it worth marking on two separate editions of the map.