It is a rath, or ringfort, the kind of enclosed farmstead that was common across early medieval Ireland, typically dating from roughly the sixth to the twelfth century. What makes this one quietly interesting is its position: wedged between drumlins that climb away to the northwest and southeast, it occupies a deliberate piece of terrain, elevated just enough to command its immediate surroundings without announcing itself dramatically.

The platform itself measures roughly 43 metres northwest to southeast and 41 metres northeast to southwest, rising between 0.7 and 1.3 metres above the surrounding ground. Around it runs a fosse, the shallow ditch that would originally have reinforced the enclosure's boundary; it survives best on the northwestern side, where it still reaches about 0.4 metres in depth and nearly six metres across the top. No original entrance has been identified, which is not unusual where vegetation and centuries of agricultural activity have softened the earthwork's edges. A field bank that had been constructed around part of the monument by 1991 was subsequently removed, and satellite imagery from 2013 confirmed its absence. About 170 metres to the north-northwest, down the slope of the col, a separate rath occupies the same ridge system, suggesting that this corner of Cloonboygher once held more than one enclosed settlement in relatively close proximity.