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, or occasionally a place of more ceremonial significance. Thousands of ringforts survive across Ireland, most dating from the early medieval period, roughly the fifth to the twelfth centuries, yet each one carries its own particular character depending on how well it has been preserved, what the surrounding terrain reveals, and how much of its original form can still be read in the stonework.

The cashel at Durless belongs to this widespread but endlessly varied tradition. Stone-built enclosures of this kind were typically the homes of farming families of middling status, their walls serving as a boundary against livestock straying and as a visible mark of ownership and occupation. In the west of Ireland, where good building stone is rarely far from the surface, cashels are more common than their earthen equivalents, and the Mayo landscape holds a considerable number of them, many in varying states of survival. Without further documentary or excavated evidence, the specific history of this particular site, its occupants, its date of construction, and any associated finds or features, remains largely unrecorded in the public domain.