The site is a rath, the most common form of ringfort in Ireland, built by enclosing a roughly circular area of ground with an earthen bank and a fosse, which is the shallow external ditch dug to provide material for the bank and to mark the boundary of the enclosed space. This one measures approximately 33 metres north to south and 37 metres east to west, making it a fairly typical example in terms of scale. The bank still stands around 1.2 metres high, and the fosse, though shallow at about 0.2 metres deep, survives along the north-eastern to south-eastern arc.

Raths were built primarily during the early Christian period in Ireland, roughly between the fifth and twelfth centuries, and most likely served as enclosed farmsteads for a single family or small household. The choice of this particular location follows a pattern seen repeatedly across Ireland: the enclosure sits atop a north-to-south running ridge, giving the occupants a natural vantage point over the surrounding ground. That practical logic, applied by farmers working this part of Mayo more than a millennium ago, is what accounts for the slight but unmistakable elevation still visible from the field today.