This one on the lower slopes of Kilronan Mountain in County Roscommon does not. The enclosure is D-shaped rather than fully round, its straight western side reinforced by a fosse, a defensive ditch roughly four metres wide and nearly a metre deep, and a low outer bank beyond that. Yet nowhere along the perimeter is there any visible break to suggest how its inhabitants once came and went.

The monument sits on a north-facing shelf near the foot of Kilronan Mountain's south-facing slope, an arrangement that would have offered some shelter from prevailing weather while keeping the ground reasonably level. The enclosure itself is modest, measuring roughly eighteen metres east to west and just under eighteen metres north to south, its boundary defined by a scarp, a slope or cut edge in the ground, that rises most prominently at the northern arc where it reaches about one and a quarter metres. On the eastern side this scarp is revetted, meaning faced or reinforced, with stones, a detail that suggests some care in its original construction. Inside the enclosure, a small rectangular house site survives as a low earthen bank, open on its eastern side, internally measuring roughly five and a half by four and a half metres. The combination of a defined domestic interior within a defended perimeter is typical of early medieval Irish raths, which functioned as farmsteads for free farming families rather than as purely military structures.

The whole monument now sits in the middle of a coniferous plantation, though a cleared area around it has kept the trees from encroaching directly onto the earthworks. That clearing preserves the archaeology but also gives the place an oddly theatrical quality, the grass-covered enclosure and its bushes sitting in a small pool of daylight surrounded by ranked conifers, with no clear entrance in sight.