At Coolagh in County Galway, a cashel once stood on karstic limestone terrain, a type of landscape characterised by porous, fractured rock that produces thin soils, rocky outcrops, and the kind of rough scrub and grassland common across much of the Burren and its fringes. A cashel is a stone-walled ringfort, roughly circular in plan, typically built during the early medieval period to enclose a farmstead or small settlement. This one, approximately thirty metres in diameter, is gone.

The enclosure was still visible enough to be mapped on the first edition of the Ordnance Survey six-inch sheet, which places its existence as a recognisable feature in the nineteenth century. By 1986, when Casey documented it, the site had been destroyed by industrial quarrying. The same karstic geology that once shaped the landscape around the cashel made the ground beneath and around it commercially attractive; limestone quarrying has been a significant industry across this part of Galway. The monument was also the subject of a clerical error in the regional inventory, having been assigned an incorrect reference number, a small administrative footnote that nonetheless speaks to how easily a site can slip between the cracks of institutional memory.

There is nothing to see at Coolagh today, at least not of the cashel itself. What remains is the record of an absence, a circle on an old map, a note in an inventory, and the quarried ground where the walls once stood.