Most examples of these early medieval enclosed farmsteads, built roughly between the fifth and twelfth centuries, still announce themselves with a raised circular bank and a sense of enclosure. The one at Ballynabortagh in County Cork asks more of you. It sits in pasture on a south-west-facing slope, and what survives is barely a whisper of the original construction: a roughly circular area measuring about 43 metres north to south and 37 metres east to west, defined by a low earthen bank that rises only half a metre on the interior and a mere quarter of a metre on the exterior. It has been levelled, most likely through centuries of agricultural activity, until the enclosure is less a visible structure than a faint interruption in the grass.

A ringfort, or rath, was the standard form of defended homestead in early medieval Ireland, typically surrounding a farmhouse and its outbuildings with one or more earthen banks and ditches. The earthworks at Ballynabortagh follow that circular template, and there is still a shallow depression outside the bank to the north-north-west, likely the remnant of the original fosse, the ditch that would once have reinforced the boundary. That such a slight trace persists at all is partly a function of terrain: slopes tend to preserve low earthworks better than flat ground, since they discourage the kind of repeated heavy ploughing that obliterates such features entirely on more workable land.