The ringfort at Kinmona in County Galway is precisely that. It survives today only as a grid reference in level pastureland, the earth around it giving no indication that anything of significance ever stood here.

The 1838 edition of the Ordnance Survey six-inch map recorded a circular enclosure roughly thirty metres in diameter, and inside it, something the cartographers marked simply as a 'Cave'. That cave was almost certainly a souterrain, an underground stone-lined passage or chamber built in association with early medieval ringforts, typically used for storage and occasionally as a refuge. A rath, to use the Irish term, was a circular earthwork enclosure, usually defined by a bank and ditch, within which a family or household would have lived during the early medieval period. Writing in 1952, McCaffrey catalogued the site as an 'Earthen fort (?)', that question mark already signalling doubt, and noted the souterrain while observing that nothing remained of the fort itself. By that point, field clearance had already done its work. Whatever banks, ditches, or underground stonework once defined this place had been levelled and removed, absorbed into the agricultural landscape around it.