What makes the example at Carrowreagh quietly anomalous is the way its builders worked the landscape against itself. Positioned at the break of slope above a natural north-east-facing scarp, the enclosure commands views in every direction, and on the north-east side the need for defensive earthwork diminishes almost entirely, the land simply falling away beyond a reduced fosse that narrows to little more than a terrace before the ground drops sharply on its own. Whoever chose this site understood that the hillside could do part of the work.

The site appears on Ordnance Survey six-inch maps from both 1838 and 1929 under the name Cross Fort, though no explanation for the name survives in what is recorded about it. The enclosure itself is a broadly oval area, roughly 31 metres north to south and 35 metres east to west, ringed by a substantial bank of earth and stone, a fosse (the ditch surrounding a ringfort, typically cut to make the outer face of the bank more imposing), and a lower external bank beyond that. The inner bank is noticeably more formidable from outside than within, rising up to two metres on the external face in places, while sitting almost flat on the interior. At the north-east, where the natural scarp takes over, the bank has been reduced to a remnant, and stones protruding from its outer face suggest it was once given a stone facing. A gap on the south-east side, roughly two and a half metres wide in the inner bank and wider still in the outer, is probably the original entrance, though a low line of sod-covered stones now extends across it. Later field boundaries on the south-south-west to north-north-west have been built incorporating the external bank, following its curve rather than cutting across it, which suggests those who farmed here afterwards recognised the line of the old structure and chose to work with it.

The interior is slightly raised at its centre and noticeably uneven underfoot. The north-east quadrant is crossed by low scarps and banks that appear to be later additions rather than original features, and a circular depression about eight metres across sits in the north-west quadrant, possibly the result of more recent disturbance. The inner bank carries hawthorn, gorse, and brambles, which is common enough on earthworks that have been left undisturbed for long enough to develop their own scrubby ecology.