The one at Clogher in County Kerry is a rath, the earthen variety of ringfort, distinguished from its stone-built cousins by a circular bank and ditch thrown up from the surrounding soil rather than dry-laid masonry. That simplicity of construction is part of what makes them so easy to overlook and so quietly persistent in the landscape.

Raths were the typical enclosed farmsteads of early medieval Ireland, in use roughly between the fifth and twelfth centuries, and they served as protected living spaces for a family and their livestock rather than as military fortifications in any serious sense. The bank and ditch offered a degree of security against opportunistic cattle-raiding, which was a genuine and recurring concern in Gaelic society of the period. Kerry has a particularly dense concentration of such monuments, the peninsula's topography having supported a dispersed pattern of small farming communities for well over a millennium. Clogher, as a placename, derives from the Irish clochán or clochar, words associated with stony ground or a stone structure, which hints at the character of the local landscape even if the rath itself is earthen.