The rath at Ballinvilla in County Mayo is one such site, a circular enclosure of the kind that would have served as a defended farmstead during the early medieval period, roughly between the fifth and twelfth centuries. These structures typically consisted of one or more raised earthen banks, sometimes reinforced with stone, enclosing a central living area where a family and their livestock would have sheltered. Thousands survive in various states of preservation across Ireland, though many have been lost to agricultural change over the centuries.

The Ballinvilla example sits within a county that contains a remarkable density of prehistoric and early medieval remains, from megalithic tombs on the Céide Fields plateau to the iron-age enclosures of the western seaboard. A rath of this type would have been the home of a relatively prosperous farming family, its banks and ditches serving as much as a marker of social status as a practical defence against cattle raiders. The precise condition, dimensions, and history of this particular site remain difficult to pin down from available sources, which means the monument retains a certain quiet anonymity even among those with an interest in the archaeology of the region.