The structure is a cashel, meaning a ringfort built from stone rather than earthen banks, and this one has retained enough of its double-faced wall to give a clear sense of its original form, even if much of that wall has collapsed into the broad spread of tumble that now surrounds it.

The cashel is roughly circular, measuring 21.7 metres north to south and 20.9 metres east to west, with a wall that survives to somewhere between half a metre and 0.7 metres in height and around a metre wide at its western face. The total spread of collapsed stone reaches between three and four metres across in places, suggesting the wall was once considerably more substantial. A gap of 4.5 metres in the wall on its west-northwest to northwest side is thought to be a later alteration, cut through after the cashel had gone out of use as a settlement. Immediately outside this gap, a small rectangular enclosure measuring roughly eight metres by six metres was added at some point, making use of the breach as a point of access or enclosure in its own right. The site appears on both the 1897 Ordnance Survey 25-inch plan and the 1920 edition of the six-inch map, and grass-covered field walls running up to the cashel from the east and southwest suggest the surrounding field system continued to incorporate the old structure long after its original purpose had passed. Another enclosure lies approximately 94 metres to the southeast, hinting that this corner of Ballyganner was once considerably more organised and densely occupied than the rough pasture there today might suggest.