The feature was recorded on the Ordnance Survey's six-inch map of 1838, then dropped from all subsequent editions, which gives it an oddly provisional quality, as though the surveyors who came after had decided it no longer warranted the attention. What remains is a roughly circular area, approximately 38.5 metres north to south and 40 metres east to west, defined by a low bank and an outer fosse, the latter being a shallow ditch dug around the exterior of the bank. Even where best preserved, on the south-east to south-west arc where the bank is cut into the rising hillside, the bank rises only 0.3 to 0.4 metres above the interior and the fosse reaches barely 0.3 metres in depth. Elsewhere around the circuit, both features fade almost to nothing.

The hill itself, named Barrett's Hill on the 1929 Ordnance Survey map, sits in a geographically compressed bit of landscape. A larger ridge immediately to the north pinches off views in that direction, leaving only a narrow east-west pass between the two. To the south, the slope drops away to an inlet of Clew Bay roughly 250 metres below, though a clear view of the bay and of Croagh Patrick beyond is limited and oblique rather than panoramic. The interior of the enclosure follows the concave tilt of the hill, falling steeply from south to centre before levelling out toward the north. Relict cultivation ridges, the raised parallel strips left by historic spade or plough farming, cross the bank and fosse on the west side, indicating that the enclosure had fallen out of use or recognition long before the land was put to tillage. A later field bank bisects the eastern edge. About 30 metres downslope to the north lies a separate rath, a type of circular earthen ringfort common in early medieval Ireland, and the relationship between the two features is unresolved. The function and date of the enclosure remain unknown.