A cashel is a ringfort built from dry-stone masonry rather than earthen banks, a distinction that places it within a tradition of early medieval settlement common across the west of Ireland, where good building stone was easier to come by than deep, workable soil. These enclosures, typically dating from roughly the fifth to the twelfth centuries, served as farmsteads for individual families or small kin groups, the circular wall defining a boundary between the household and the wider, less certain world beyond it.

Beyond its classification as a cashel type ringfort in the townland of Ballynastaig, the specific history of this particular site remains difficult to recover. No detailed excavation records or historical accounts appear to have been published, and the monument exists in that large category of Irish archaeological sites that are known to survive but have not yet been closely studied. Galway's western parishes contain a considerable density of such structures, many of which have never been formally surveyed at ground level, their stonework slowly merging back into field boundaries or becoming overgrown to the point where the original form is hard to read from close up.