Where a roughly 25-metre circular enclosure once sat in low-lying marshy pastureland, a large quarry now occupies the ground. Nothing visible survives at the surface, and the site is, in practical terms, gone.

Ringforts, which are circular enclosures typically defined by an earthen bank and ditch, were the most common form of rural settlement in early medieval Ireland, used as farmsteads and homesteads from roughly the fifth century onwards. The one at Carn was recorded on the Ordnance Survey six-inch maps, the extraordinarily detailed series produced across Ireland from the 1830s, which captured the outlines of countless earthworks that have since been lost to agriculture, development, and extraction. At Carn, it was the quarry that did the damage. The marshy, low-lying ground around the site might once have offered some incidental protection, as waterlogged conditions tend to slow agricultural improvement, but it was not enough.