What looks at first glance like a low, tree-fringed mound is in fact a rath, an early medieval ringfort of the kind that once numbered in the tens of thousands across Ireland. These were the enclosed farmsteads of farming families, built roughly between the fifth and twelfth centuries, their earthen banks and ditches marking out a domestic space for people, livestock, and perhaps a few timber buildings. This particular example at Cappanihane sits on a gentle rise in otherwise level ground, its circular form still legible despite centuries of erosion and agricultural pressure.

The site was recorded and compiled by Denis Power, with notes uploaded in August 2011. The enclosure measures approximately 44 metres north to south and 40.5 metres northeast to southwest, making it a reasonably substantial example of its type. The earthen bank that defines the perimeter survives to an internal height of around 0.6 metres and an external height of 1.8 metres, which gives a sense of how the bank would once have appeared considerably more imposing from outside than from within. Beyond the bank runs an external fosse, the term for the accompanying ditch, here roughly 0.8 metres deep and 1.7 metres wide. At the western side of the bank there is a break roughly 3 metres wide, which may represent the original entrance, possibly with a causeway crossing the fosse, though this area has been recently disturbed by agricultural activity and is difficult to read clearly.

Access is through working pasture, so the usual courtesies of farmland apply. The interior of the enclosure slopes gently downward from the perimeter toward the centre, a subtle topographic detail that becomes apparent only once you are standing inside it. Both the interior and the enclosing bank are partially covered by trees and undergrowth, which simultaneously obscures the earthworks and, in a roundabout way, has helped protect them from the plough. Visiting in late winter or early spring, before the undergrowth fills in, gives the clearest view of the bank's profile and the line of the fosse. It is worth walking the full circuit of the exterior to appreciate how the earthwork reads from the outside, where the bank height is most pronounced.