It is a sweathouse, a type of structure once common across Ireland but now largely forgotten, and its purpose was straightforwardly therapeutic. Fires were lit inside to heat the stone walls, the ash was raked out, and a person suffering from rheumatism or similar ailments would crawl in through the low entrance and sweat, before emerging to plunge into cold water nearby. The spring beside this one would have served exactly that purpose.

The structure itself is built directly into the slope, a technique that allowed the hillside to act as insulation and structural support. Inside, the chamber measures just 1.17 metres by 1.26 metres, with a height of 1.55 metres, barely enough to stand upright. The walls are vertical and the roof is lintelled, meaning it is formed from flat slabs of stone laid horizontally across the top rather than corbelled or arched. The entrance on the eastern side is narrower still, 0.55 metres wide and 0.6 metres high, meaning anyone entering had to crouch considerably. A farmstead stood roughly 30 metres to the east, suggesting this was working infrastructure attached to a specific household rather than a communal facility, though a second sweathouse lies approximately 240 metres to the west-south-west, which hints that the practice was sufficiently established in this area to warrant more than one.