It is a rath, which is to say a roughly circular earthen enclosure built during the early medieval period, typically to enclose a farmstead and its associated buildings. Most were constructed between roughly 500 and 1000 AD, and tens of thousands once dotted the Irish landscape, though relatively few have come through in such readable condition.

This particular example at Liscuill is subcircular in plan, measuring approximately 30.5 metres east to west and 25.8 metres north to south. It is defined by an earthen bank with an external fosse, the fosse being the ditch dug just outside the bank, the spoil from which was typically thrown inward to raise the bank itself. The southwestern arc of the bank is the best preserved section, retaining something of its original profile. To the east and south, the fosse no longer reads as an open depression but survives as a band of different vegetation, the kind of subtle trace that aerial photography and careful ground survey can pick out long after the physical earthwork has softened. Several breaches in the bank are present, though these appear to be of modern origin rather than any meaningful ancient disruption.