The ringfort at Three-Gneeves is a rath, the common Irish term for an enclosed farmstead of the early medieval period, typically consisting of a bank and ditch surrounding a domestic area. What makes this one quietly interesting is the evidence of two separate phases of land use occupying the same ground, each leaving its mark in a different way.

The structure is roughly circular, measuring 31.5 metres north to south and 31 metres east to west, making it a reasonably substantial example of the type. An earthen bank, still standing to a height of 2.05 metres along its south-south-west to north arc, forms the main enclosure; elsewhere the boundary survives as a scarp, a slope rather than a raised bank, suggesting the earthwork has eroded or was never uniformly built up on all sides. Outside the bank, a fosse, that is, a ditch, runs from the south-south-west around to the north-north-west and survives to a depth of 0.6 metres. The site sits on a south-south-east-facing slope, a typical orientation for these enclosures, which were often positioned to catch light and drain well. Crossing the interior on a north-west to south-east axis are cultivation ridges, the parallel raised beds associated with later spade tillage, suggesting that at some point after the rath fell out of use, the enclosed ground was turned over to growing crops rather than left undisturbed.

The cultivation ridges inside the bank are the detail worth pausing on. Ringforts were largely abandoned as a form of settlement by the end of the early medieval period, and the decision to plough or ridge the interior of one suggests a later community treating the old enclosure simply as convenient, already-cleared ground. The bank was high enough to shelter the beds; the fosse was perhaps useful for drainage. The rath at Three-Gneeves now sits in pasture again, the ridges fossilised beneath the grass, both features visible as surface earthworks to anyone who looks carefully at the ground.