On an east-facing slope in undulating pastureland just north of Cartron House in Beagh, County Galway, there is a ringfort that has essentially ceased to exist above ground. No earthwork, no bank, no ditch; nothing a passing walker would notice. What remains is, in a sense, purely cartographic.

A ringfort, or rath, is one of the most common monument types in the Irish landscape, typically a roughly circular enclosure defined by one or more earthen banks, used as a farmstead during the early medieval period, broadly between the fifth and twelfth centuries. This particular example was recorded on the first edition of the Ordnance Survey six-inch map as a roughly circular enclosure approximately thirty metres in diameter. That survey, carried out in the nineteenth century, captured the feature at a moment when it was still legible as a shape in the land. Sometime between that mapping and the present, whatever surface trace survived was lost entirely, most likely to agricultural activity in the intervening generations. The slope, the pasture, the proximity to Cartron House; these details locate it precisely, but the thing itself is gone.