What they would be missing is a cashel, a type of ringfort defined by a stone rather than an earthen boundary wall, and this one has largely disappeared back into the landscape it once commanded. Only a short arc of drystone walling survives from the north to the east of the circuit; the rest of the enclosure is marked by nothing more than a scarp, a low natural-looking slope in the ground that is, in fact, the eroded ghost of a substantial stone wall.

The monument measures roughly 35 metres in diameter, which is a fairly typical footprint for a cashel of early medieval date. These enclosures were built primarily between the sixth and tenth centuries and served as enclosed farmsteads, protecting a household, its livestock, and its stores. This one, however, has been further compromised by a field boundary that cuts across it at both the north-east and south-east, meaning later agricultural organisation has physically sliced through the fabric of the older structure. Around 300 metres to the east lies a second ringfort, suggesting that this part of Tonacooleen once supported more than one enclosed settlement in relatively close proximity, a pattern not uncommon in the Irish landscape where good ground was worth occupying and defending across generations.