The one at Coolnagour in north Cork has nearly vanished, absorbed so thoroughly into the working landscape that the fence lines of surrounding fields now run directly over what was once its defining bank.

Ordnance Survey mapping charts its slow erasure with some precision. The 1842 six-inch map recorded a clear hachured circular enclosure roughly 45 metres in diameter, the standard shorthand cartographers used to show a raised earthwork. By the time surveyors returned in 1904 and again in 1936, the picture had already changed: the inner area had reduced to a circular raised area of around 30 metres, wrapped by a second external scarp still reaching the original 45-metre diameter, but with a field boundary now cutting across it from south-southeast to north-northwest. The enclosure was being parcelled up, its edges conscripted into the practical geometry of agricultural land division. What survives today is an arc of earthen bank, running roughly south to north across a length of about 44 metres, standing about a metre high on its interior face. A shallow external fosse, the ditch that once accompanied the bank, remains faintly legible at a maximum depth of 0.2 metres. The bank itself is heavily overgrown and has been incorporated into the surrounding field fence system, making it difficult to read as an archaeological feature at all.

The site sits on a gentle south-west facing slope in pasture, which is exactly where you would expect an early medieval farming enclosure to be, oriented to catch light and positioned on workable ground. What makes Coolnagour quietly instructive is precisely its ordinariness and its near-disappearance. The OS maps preserve a before-and-after record that most levelled sites never have, allowing a reasonably clear reconstruction of what was lost between one survey and the next.