A cashel is simply a ringfort built from stone rather than earth and timber, the word itself coming from the Latin castellum by way of early Irish. Where an earthen ringfort raises a bank and ditch, a cashel raises a dry-stone wall, sometimes several feet thick, enclosing a roughly circular space that would once have sheltered a farmstead, its outbuildings, and its livestock. Thousands of these survive across Ireland, most dating from the early medieval period, roughly the fifth to the twelfth centuries, yet each one occupies its particular patch of ground in its own particular way.

Clydagh is a small townland in the west of Mayo, a county that has a notable concentration of stone enclosures given the thin soils and ready availability of field stone across much of its terrain. The cashel here belongs to a tradition of rural settlement that predates the arrival of Anglo-Norman manorial organisation by many centuries. The families who built and used such enclosures were farmers and cattle-keepers operating within a Gaelic social structure in which the ringfort, whether earthen or stone, served as both a working farmyard and a statement of household status. The thickness and height of the wall, and whether it was accompanied by an outer enclosure called a bawn, could signal something about the wealth or standing of whoever lived within.