Somewhere on a south-south-west-facing pasture slope in north Cork, overlooking a stream, a ringfort once stood. A rath, as this type of earthwork is commonly called, is a roughly circular enclosure defined by an earthen bank and external ditch, typically dating to the early medieval period and associated with a single farmstead or small settlement. This one measured approximately thirty metres across. By 1983, it was gone, levelled by agricultural work after years of standing as a raised, bush-choked mound.

The site had been quietly documented for decades before its destruction. Ordnance Survey maps from 1905 and again from 1935 recorded it as a hachured circular raised area, the small radiating lines indicating an earthen mound rising above the surrounding ground. That it survived into the twentieth century, albeit overgrown and presumably long since cleared of any structural remains, makes its loss in 1983 feel all the more pointed. What the maps preserved, the land swallowed.

The story does not end entirely there. Aerial photography has since revealed the site's ghost in the form of a cropmark, the circular outline of the fosse, the outer ditch that once defined the enclosure's edge, still traceable as a difference in how the grass or crops grow above the buried feature. A fosse filled with disturbed earth retains moisture differently from the undisturbed ground around it, and in the right season, under the right light, the shape reappears. The ringfort at Ballynacaheragh is visible now only from the air, a circle pressed faintly into the field, readable only in photograph.