What survives is a partial arc of drystone walling, tracing roughly from the south-south-west around to the north-west, the rest of the perimeter having vanished so completely that no surface trace remains to the east at all. The monument measures around 39 metres in diameter, which would once have made it a substantial structure, yet what a visitor encounters today is closer to a suggestion than a ruin.

This is a cashel, the term used in Irish archaeology for a ringfort built from stone rather than earth and timber. Ringforts were the dominant form of rural settlement in early medieval Ireland, typically dating from roughly the sixth to the twelfth century, and thousands survive across the country in varying states of repair. A cashel of this diameter would likely have enclosed a farmstead, perhaps with ancillary outbuildings and a surrounding wall intended as much to define territory and signal status as to provide serious defence. The particular damage at Carrownacroagh appears to have a prosaic cause: the townland boundary, a legal and administrative line drawn across the landscape, cuts directly through the monument at both the south-south-west and north-west, precisely the points where the walling breaks off. Land division and agricultural clearance have conspired over the centuries to erase the eastern half of the enclosure entirely.