Captured on the Ordnance Survey's six-inch map of 1842 as a circular enclosure roughly 38 metres in diameter, it was already noted as having its interior planted at that time. Since then, the main body of the fort has been levelled entirely, leaving only fragments to indicate what once stood here.

Ringforts, known in Irish as raths, were enclosed farmsteads typically dating from the early medieval period, roughly 500 to 1200 AD. They consisted of a raised circular bank with an outer fosse, or ditch, defining a domestic space within. At Cooldurragha, the bulk of that structure is gone, but an arc of the original earthen bank survives, absorbed into the field fence system to the south-west of the old garden. The bank still stands to around 0.8 metres on its interior face and 0.85 metres on the exterior, while the accompanying fosse reaches a depth of 1.15 metres. That last figure may be slightly misleading as a guide to the original monument, since the fosse appears to have been deepened at some point to serve as agricultural drainage, a fate that befell many such features as land was improved in the post-medieval centuries.

What remains is not dramatic by any standard measure, yet the survival of even this partial arc within a working field boundary is a reminder of how thoroughly early medieval settlement geography was folded into the later farming landscape. The earthwork was not erased so much as repurposed, its ditch pressed into service, its bank becoming a convenient division between fields, the circular logic of its original plan now only legible if you know what to look for.