At roughly twenty metres long, eight and a half metres wide, and over two metres at its highest point, it is substantial enough to catch the eye, yet easy to mistake for a natural rise in the ground. It is, in all likelihood, the remains of a lime kiln, a structure that was once central to agricultural life across rural Ireland.

Lime kilns were used to burn limestone at high temperatures, producing quicklime that farmers spread across acidic soils to improve fertility. They were common features of the post-medieval countryside, and this example at Rathlogan is thought to date to after 1700. The arched stone chamber visible on the western side would have served as the draw hole, where the finished lime was raked out once firing was complete. The use of roughly hewn rather than dressed limestone blocks gives the structure an unfussy, functional character, built to work rather than to impress. That it survives at all, in recognisable form and with its arch intact, is more than can be said for many of its counterparts elsewhere.