Quarrying on the western side of a ringfort, one of those circular earthwork enclosures built during the early medieval period as a farmstead and defensive boundary, cut through the site and opened up a souterrain, an underground tunnel or chamber constructed from stone and covered with flat capstones laid across the walls as a roof. These subterranean structures are found across Ireland and were typically used for storage, refuge, or both. This one, running eastward beneath the earth, had kept its secret until the machinery arrived.

The ringfort it belonged to had already been levelled by the time the souterrain came to light, the earthworks flattened in the process of quarrying. What the digging revealed was a lintelled passage, its stone walls and covering slabs intact enough to identify its form and direction. It is a common enough story in Irish archaeology, where the disturbance of one thing uncovers another, and where agricultural or industrial work has repeatedly brought early medieval structures into an accidental kind of daylight. The souterrain has since been infilled, returned to the ground it briefly surfaced from, leaving no visible trace at the site.