A rath, to use the Irish term for an earthen ringfort, is a roughly circular enclosure defined by one or more banks and ditches, built during the early medieval period as a farmstead or place of status. At Cooga, the road does not skirt the monument or clip its edge; it bisects it, following a north-south line that also happens to mark the townland boundary between Cooga Upper and Cooga Lower. The ancient enclosure and the administrative boundary have, over centuries, come to share the same line in the landscape.

The ringfort was recorded on the first edition Ordnance Survey six-inch map of 1840 as a substantial circular enclosure with a diameter of approximately 61 metres, and at that point the bisecting road was already present, cutting across the western half. By the time the OS 25-inch map was produced, only the western arc of the monument was depicted, a surviving section running roughly 36 metres from north-northwest to south-southeast, defined on its eastern side by the road itself. The eastern half of the original enclosure had, for mapping purposes at least, effectively ceased to be recorded. The site sits in undulating pasture, and more recent satellite imagery from Digital Globe and Google Earth, examined between 2011 and 2018, shows the remaining western portion further enclosed by a newly constructed access road leading to a dwelling nearby. The record was compiled by Alison McQueen and Vera Rahilly and uploaded in July 2020.

Because the monument straddles a public road and a townland boundary, locating it on the ground is reasonably straightforward; the road itself is, in a sense, the marker. The visible remains lie immediately to the west of the road, presenting as a segmental or curved earthwork in the pasture. Visitors should be aware that the surrounding land is private farmland, and the encroachment of modern infrastructure means the surviving portion gives only a partial impression of the original scale. Aerial or satellite images are genuinely useful here, offering a clearer sense of the arc that once formed a complete circle 61 metres across.