The site at Ballynacroghy is a rath, the Irish term for a ringfort, a type of enclosed farmstead typically built between roughly the fifth and twelfth centuries. What makes this particular example quietly compelling is the evidence of deliberate reshaping: a natural elevation was enhanced and built up to create an oval platform, approximately 44 metres north to south and 38 metres east to west, enclosed within two substantial earthen banks with a fosse, or ditch, running between them. A slight external fosse adds a further layer of enclosure beyond the outer bank.

The earthworks have not survived evenly. The inner bank remains visible along the south-east to western arc but has been levelled elsewhere, and the inner fosse itself has been filled in at the west-south-west. The outer bank shows signs of having been deliberately steepened along its northern and south-eastern side, while it has been almost entirely levelled from the east. Inside the enclosure, faint traces of cultivation ridges run roughly east to west, suggesting the interior was later turned over to agricultural use at some point after the monument fell out of its original function. Near the centre, a large stone juts up through the turf, with two flat stones lying on the surface close by; whether these belong to a buried structure beneath or are later intrusions is not recorded. The site sits 45 metres east of a stream marking the old townland boundary with Kilbixy, and the 1837 Ordnance Survey six-inch map records a small clustered settlement called Clontane just 180 metres to the south-west.

The monument does not sit alone in this stretch of countryside. Within a few hundred metres lie a second ringfort, a mound barrow, and St. Bigseach's Well to the north-north-east, a grouping that suggests this area carried real significance in the early medieval and possibly pre-Christian landscape of the Kilbixy district. The views opening out to the south, west, and north-west from even this modest rise would have made the position legible across the surrounding low-lying land, which is perhaps exactly the point.