When the Ordnance Survey mapped it in 1842, their draughtsmen recorded a bivallate enclosure, meaning one defined by two concentric banks with a fosse, or ditch, between them. By the time the same landscape was surveyed again in 1905 and 1937, the outer works had diminished enough that the cartographers drew it as univallate, a single-banked enclosure, with only a partial external fosse running from the south-south-east around to the north-north-east. The earthwork had not vanished, but it had faded in the intervening decades, most likely through the slow attrition of agricultural use.

Ringforts, known in Irish as raths when built from earth rather than stone, were the most common form of enclosed farmstead in early medieval Ireland, typically dating from roughly the fifth to the twelfth centuries. This example at Kilcanway sits on a gentle south-facing slope in pasture, and its core dimensions have remained legible: the interior is a near-perfect circle of 35.7 metres across in both directions. The inner earthen bank still stands 1.7 metres high on the interior face and about 1.55 metres on the exterior, with a shallow fosse around 0.4 metres deep between it and what survives of the outer bank. That outer bank, now only 0.4 metres high, persists to the south-west, which is where the map evidence and the surviving earthwork best corroborate one another. There is a break in the bank to the south-east, the kind of gap that often marks an original entrance, though it can also result from later interference.

The interior is grass-covered and the inner bank is partially overgrown, which gives the enclosure a settled, softened quality rather than a sharply defined archaeological profile. The shift in how successive surveys recorded it is itself a small lesson in how field monuments are not static objects but things that change, are interpreted differently, and gradually yield their outer details to the land around them.