These structures appear across Ireland in considerable numbers, usually associated with nearby settlement sites, and were likely used for storage, refuge, or both. The one at Caurans is recorded as a monument, which means someone, at some point, identified and noted its presence. Beyond that, the details remain quietly out of reach.

Souterrains were generally constructed by lining an excavated trench with drystone walling and roofing it with large flat slabs, then covering the whole thing over again with earth. They can be simple single passages or more complex arrangements with multiple chambers and low connecting crawlways designed to slow down anyone attempting entry by force. In Mayo, as elsewhere in Ireland, they tend to survive as slight depressions or irregular ground disturbances, sometimes only fully understood when examined below the surface. What drew early medieval communities to the Caurans area, what settlement stood nearby, and what the souterrain's internal arrangement looks like are questions that the available record does not currently answer.