There is a ringfort in Ballydonagh, County Waterford, that has effectively vanished from the landscape while remaining visible on paper. A ringfort, to give the briefest of explanations, is a roughly circular enclosed settlement, typically of early medieval date, defined by one or more earthen banks and ditches. Thousands survive across Ireland, many of them prominent features in the countryside. This one is not. It sits in tillage ground on a south-west-facing slope, and at ground level there is simply nothing to see.

What we know of it comes from the first edition of the Ordnance Survey six-inch map, published in 1840, which records a small circular embanked enclosure with an external diameter of approximately thirty-five metres. That the nineteenth-century surveyors could mark it suggests the earthworks were at least partially legible at that time. Since then, cultivation of the surrounding land has levelled whatever remained above the surface. The enclosure now exists more as a cartographic fact than a physical one, a feature preserved in map archives rather than in the soil.