It is a booley hut, the kind of rough shelter built for transhumance, the old Irish practice of moving cattle to upland grazing each summer, with a family member, often a young woman, accompanying the herd and living on the mountain for the warmest months. The hut is modest by any measure: an interior space of roughly 1.6 metres by 2 metres, drystone walls a full metre thick, and a door opening on the east wall just wide enough to squeeze through. That thickness, out of all proportion to the tiny interior, tells you something about the weather these mountains can produce.

The structure appears on Ordnance Survey six-inch maps from both 1905 and 1937, marked as a rectangular building, which means it was still recognisable as something purposeful well into the twentieth century, even if booley farming itself had largely faded from practice long before then. Drystone construction, which uses no mortar, relies entirely on the careful placement of stones to hold its own weight, and the fact that walls here survive to nearly a metre in height after what was likely a century or more of abandonment says something about the care taken in building it. These huts were working structures, not ceremonial, and were rarely built to last beyond the season, which makes the ones that do survive quietly remarkable.