Roughly rectangular and standing 3.5 metres at the front, with a width of around 4.2 metres, it is not a small structure. The southern face carries a lintelled recess, an arched or beam-topped opening used to rake out the finished product, measuring 1.5 metres high, 1.9 metres wide, and over two metres deep. Behind it, sloping slabs lead to what was once the funnel, the upper bowl where limestone and fuel were loaded in alternating layers and set to burn. That funnel is now almost completely infilled.

A lime kiln was a working piece of agricultural infrastructure, used to burn limestone at high temperatures to produce quicklime, which was then spread on fields to reduce soil acidity, a practice that transformed the productivity of Irish farmland from the eighteenth century onwards. They were built in enormous numbers across the country, often close to a road or crossroads for ease of access, and this one at Carrigacooleen follows that practical logic precisely. It appears on the Ordnance Survey six-inch map of 1842, meaning it was already a established feature of the landscape at a moment when much of rural Ireland was on the edge of catastrophic change. The kiln itself would have predated that survey, though by how much is not recorded.