A cashel or cahir is a ringfort built of stone rather than earth, a type common across Munster and associated broadly with early medieval settlement, and this one is built to an impressive scale. Its circular enclosure measures roughly 34 metres across internally, the surrounding bank standing up to 3 metres above the interior and 4 metres above the outer ditch. That external fosse, 2.5 metres wide and 1.5 metres deep, still encloses most of the site; only to the north-west has it been broken, where a later fieldbank cuts across both it and the main wall.

What makes the site particularly interesting is what has emerged from beneath it over the years. In the early 1880s, a Miss Hickson recorded the discovery of a large flat stone below the surface of the interior; when removed, it revealed a stone-lined well of considerable depth. Then, in 1896, P.J. Rice described his own excavation work in the fosse on the south side of what he called Lisnacreavh. Digging down about three feet into the ditch, he uncovered between twenty-eight and thirty horse-loads of rough-dressed, hollowed, and burned-looking stones. Beneath that pile he found the foundations of two dry-stone walls, each roughly five feet by thirteen feet, set about five yards apart and running parallel in a southerly direction. In that same period, several fragments of inscribed stone were found within the fort by R.J. Rice and subsequently identified by the Reverend Dr Graves as portions of an ogham monument. Ogham is an early medieval script in which letters are represented by a series of notches and strokes cut along the edge of a stone, most commonly used for commemorative inscriptions in an Irish or Latin context. The interior also preserves what appear to be two rectangular stone house-sites in its northern sector, with walls around a metre thick, suggesting the cashel once supported a small domestic settlement of some kind.