The enclosure measures 37.5 metres in diameter, its bank constructed primarily of stone but now softened beneath a covering of grass. It is not a dramatic structure in the conventional sense; the external face rises only about 45 centimetres, and the interior has been left to briars, scrub, and whitethorn bushes. A gap of 6.5 metres on the south-eastern side suggests an original entrance, though the centuries have blurred its precise form.

The site sits within a landscape that was once considerably busier. About 150 metres to the north lay the ringfort of Rathanny, a bi-vallate example, meaning it was once enclosed by two concentric earthen banks rather than one. That structure has now been almost completely levelled through field clearance, leaving Ballybrannagh's enclosure as the more legible survivor of the two. A cairn, a mound of stones typically associated with burial or commemoration, occupies the crest of the same limestone reef, and the enclosure appears to have been deliberately constructed around it, suggesting the bank and the cairn were conceived as a single complex rather than separate additions. The field around the site remains slightly marshy and is used for rough grazing, conditions that have arguably helped preserve what the plough and the clearance gang have not yet reached. Michael Connolly surveyed the site as part of a broader examination of the Lee Valley area in 1996 and 1997.