A cashel is a ringfort built from stone rather than earth and timber, a circular enclosure whose thick dry-stone walls once defined the boundary of a farmstead, a family's territory, their world made tangible in local rock. Clare is good country for them. The Burren to the north is scattered with examples, and the broader county holds dozens more, each one a variation on the same essential form.

The cashel at Cooga belongs to a class of monument associated primarily with the early medieval period in Ireland, roughly the fifth to the twelfth centuries, when ringforts of all kinds served as the basic unit of rural settlement across the island. Their interiors typically contained a house or houses, perhaps a souterrain, an underground stone-lined passage used for storage or refuge, and outbuildings for livestock. The stone construction of a cashel, as opposed to the earthen banks of a rath, often reflected the local availability of material rather than any difference in status or function, though larger and more elaborately built examples could signal considerable wealth or standing.