The enclosure at Cahermacnaghten measures just 13.5 metres across at its widest north-to-south point, making it a modest structure by any standard, yet the variety of its construction is quietly interesting: large stone flags set on edge, sections of double-faced walling where two parallel faces enclose a rubble core, and stretches where the wall has simply folded under its own weight and grassed over.

The wall itself is not uniform. It averages around 0.7 metres wide, standing roughly 0.9 metres on the interior face and a somewhat lower 0.6 metres on the exterior, suggesting either differential collapse or an intentional variation in the ground level on each side. Between the north-north-east and east-south-east, the enclosing element has been removed entirely, leaving a substantial open arc. A separate gap of about 1.8 metres at the south-south-east may represent an original entrance, the kind of deliberate break in a circular enclosure wall that was typically left for access rather than caused by later disturbance. Circular stone enclosures of this general type appear across Ireland and could serve various purposes, from stock management to settlement or ritual use, though without excavation it is rarely possible to say which function applied in any given case.

The site sits on wet, rush-covered ground, which gives some indication of what a visit would involve underfoot. The rushes and the collapsed sections of walling make the circuit of the enclosure less than straightforward, but the remaining upright flags, some set directly on edge rather than laid in courses, are visible enough to give a clear sense of the structure's original shape.