Ringforts, known in Irish as raths, were typically circular earthen enclosures built during the early medieval period, most often serving as defended farmsteads for a single family or small community. This one in Corragh has drifted some distance from its original form, and that slow transformation is part of what makes it worth paying attention to.

When the Ordnance Survey mapped the area in 1839, the enclosure was recorded as roughly circular, with a diameter of around 60 metres. By the time it was examined more recently, the shape had shifted into something closer to a subrectangle, measuring approximately 55 metres on the northeast to southwest axis and 50 metres northwest to southeast. What survives is a patchwork of boundaries: a field bank running east to west along the southern side, a curved bank tracing the arc from southwest to northwest, and a scarp, essentially a steep earthen drop of about 1.5 metres, running from northwest to northeast. Beyond these remnants, the original perimeter has been absorbed into the surrounding landscape, claimed by field boundaries and time. The fort sits towards the bottom of a steep northwest-facing slope, which would have been a considered choice for its original builders, offering some natural shelter and drainage.