It is easy to overlook from a distance, but the geometry is unmistakable once you know what you are looking at: a roughly circular enclosure, measuring around 28 metres north to south and 25 metres east to west, ringed by an earthen bank that still stands close to two metres high in places.

This is a rath, the Irish term for a ringfort, the most common monument type surviving in the Irish countryside. Ringforts were typically built during the early medieval period, roughly between the fifth and twelfth centuries, and served as enclosed farmsteads for individual families or small communities. The bank at Aghyohil More is earthen for the most part but stone-faced in sections, a detail that suggests some care in its original construction. Outside the bank to the north-east, a fosse, the defensive ditch dug to provide material for the bank and to deter unwanted entry, is still visible, though it has silted up considerably over the centuries. One of the more telling small details here is that the interior has been deliberately raised on its eastern side to create a more level living surface, compensating for the natural fall of the hillslope. That practical adjustment, made perhaps fourteen hundred years ago, is still readable in the ground today.