That detail alone sets the site apart. A ringfort, or rath, is a roughly circular enclosure defined by an earthen bank and ditch, built during the early medieval period, roughly between 500 and 1000 AD, as a defended farmstead for a single family or small community. Thousands survive across Ireland in varying states of preservation. Here at Cloonanagh, the enclosure survives, but its interior has been punctured by a quarry measuring some seven metres by fifteen metres and sinking to a depth of one and a half metres, now filled with standing water.

The rath itself is a modest example. The circular raised area measures around twenty-nine metres east to west and is enclosed by an earth and stone bank roughly two metres wide. The bank stands only about thirty centimetres above the interior ground level, though externally it rises to around one and a third metres, giving a clearer sense of its original defensive intention. Beyond the bank runs a shallow external fosse, the ditch that would have added further definition to the enclosure boundary, though here it survives at only about a quarter of a metre deep. A field fence cuts across the eastern side, and from the north-west around through the north and on to the east, the bank has been worn down to little more than a scarp, a sloping edge where the earthwork has degraded over time. No trace of an original entrance survives. The quarrying of the interior, at some point after the site ceased to function as a settlement, is the kind of practical intervention that was common as land was worked and materials were extracted from convenient sources, without any particular regard for the archaeology beneath.