The enclosure measures approximately 29 metres north to south and 27 metres east to west, and what survives is a study in gradual erasure: a levelled bank on one arc, scarps of varying height on others, and a wide gap of around ten metres on the eastern side that leaves the interior open and sloping gently downward, as if the original boundary simply gave up and dissolved into the surrounding field. A faint outer fosse, a shallow defensive ditch encircling the outside of the bank, can still be traced along parts of the western and north-northwestern perimeter, though it disappears under dense furze and thorn trees to the south-southwest, where a modern field boundary has, over time, come to follow its line almost exactly.

The site takes its name from Ordnance Survey historic mapping, which records it as Ballygastell Fort, preserving a place-name that might otherwise have slipped from use as the physical remains shrank. The structure belongs to a broad class of enclosed earthworks found across Ireland, most commonly interpreted as ringforts, which were farmstead enclosures built and used predominantly between the early medieval period and the twelfth century. Their banks and ditches were less about military defence and more about marking territory, controlling livestock, and signalling the social standing of the household within. At Ballygastell, the combination of a levelled bank, surviving scarps of between 0.6 and 1.2 metres in height, and the ghostly fosse are consistent with that tradition, though centuries of agricultural improvement have worked steadily against legibility. The small gap at the north may represent an original entrance, while the much larger eastern breach has allowed the interior slope to continue uninterrupted to the outside.

The enclosure is set just off the hillock's crown, commanding views across lower, gently rolling countryside to the north-northeast and northwest. A field boundary runs roughly northeast to southwest about fourteen metres to the southeast, and the southern arc of the fosse has been absorbed into this boundary, a quiet reminder of how working landscapes and ancient ones negotiate with one another across centuries.