The site appears nowhere in that record; it showed up only when aerial imagery was examined. What stands in the pasture near Achonry is a cashel, the Irish term for a ringfort enclosed by a dry-stone wall rather than an earthen bank, and it sits on a gentle natural rise with exposed limestone bedrock breaking the surface at its south-eastern edge.

The cashel was originally roughly circular, measuring about 28 metres across in both directions, but time and agricultural practicality have done considerable work on it. The western half of the enclosing wall has been absorbed into a later rubble field wall, leaving only the eastern arc legible as archaeology. There, the old perimeter survives as a moss-covered scarp with stones occasionally pushing through the turf; at its most pronounced, near the south-east, it rises to around two metres in height and merges almost seamlessly with the natural break of slope dropping into a small damp valley below. The bedrock face itself, vertical and about 1.2 metres high, has been incorporated into the structure at the south-east, making it genuinely difficult to say where geology ends and construction begins. Inside the enclosure, a low internal scarp curves across the south-east quadrant and terminates near the centre in a low stone heap, now buried under sod, brambles, and a hawthorn bush. A barely discernible subrectangular area in the south-west interior may represent the remains of a structure within the cashel. Knocknashee, the flat-topped hill associated with prehistoric activity, is clearly visible on the northern skyline, and within 340 metres to the north-north-east lies another enclosure, while two ringbarrows sit roughly 300 metres to the south-east, suggesting this quiet corner of Sligo was once considerably more active than the forestry plantations now surrounding it would imply.