A rath, as this type of monument is known, was an enclosed farmstead typical of early medieval Ireland, constructed by banking up earth into a roughly circular rampart and digging a surrounding ditch, or fosse, on the outside. At Moanmore, that fosse survives as a flat-bottomed channel measuring just over three and a half metres wide and barely a tenth of a metre deep at its most visible, which is to say it hardly announces itself at all.

The site was identified from aerial photographs taken by the Air Corps in September 1959, which revealed what ground-level inspection would easily miss. The circular platform measures eighteen metres in diameter, defined by a gently sloping earthen scarp roughly four metres wide and only seventy centimetres high. The fosse is best preserved along the south-east to south-west arc; elsewhere it becomes extremely shallow, and along the south-west to north-north-east stretch it disappears entirely at ground level, obscured in part by a north-south field boundary bank that runs along approximately the same line as the outer edge of the original ditch. A slight dip in the scarped edge at the north-west may indicate where the original entrance once stood, though it is poorly defined. The interior slopes gently to the north, is clear of overgrowth, and now contains an ESB electricity pole planted in its south-south-east sector, a small collision of the ancient and the entirely mundane that says something about how casually such sites have been absorbed into the working landscape.