It measures only about two metres across internally, its drystone wall no more than thirty centimetres at its tallest. A narrow gap on the north-west side is likely where a door once was. To the south-west, a slightly larger subcircular space, roughly three metres across and marked by a looser, gapped arrangement of stones, appears to have served as an annex of some kind. The whole structure is modest almost to the point of invisibility, and that is precisely what makes it worth attention.

This is a booley hut, a form of seasonal shelter associated with the old Irish practice of booleying, in which farming communities would move their cattle to higher summer pastures, with herdsmen, and sometimes whole households, following along to tend them. The word derives from the Irish "buaile", meaning a milking place or summer pasture. These structures were never meant to be permanent; they were working shelters, quickly built and lightly used, which is why so many have dissolved back into the hillside over the centuries. The Cregganroe example is one of a cluster of at least ten such huts in the immediate area, all associated with a wider field system on the same ridge. Taken together, they preserve the faint outline of a seasonal economy that once animated these uplands every summer, though the landscape today gives little away beyond the bog and the rock.