It is a rath, the Irish term for a ringfort, a type of enclosed farmstead built in their thousands across Ireland during the early medieval period, roughly between the fifth and twelfth centuries. Most were home to a single farming family, the enclosing bank serving as much as a marker of status and territory as a practical defence. This one at Gearha is no longer easy to read, heavily overgrown and broken in places by animal tracks, but enough survives to give a sense of what was once a carefully constructed enclosure.

The rath measures just under 25 metres across its interior east to west. On the southern, downslope side, a natural scarp some 2 metres high does much of the structural work, while the rest of the circuit is formed by a bank of earth and stone that still stands 1.75 metres above the surrounding ground on its outer face, though it drops to less than a metre on the interior side. The bank has a basal width of 2.6 metres and retains traces of drystone revetment, rough coursed stonework used to face and stabilise the earthen core, with some flat slabs set upright along short stretches on the eastern and western interior. A shallow fosse, a defensive ditch, can still be traced running from the south around to the west; it is 1.25 metres wide and half a metre deep. Field walls branch away from the rath at the north and east, suggesting the site was later absorbed into the working landscape of the area, its ancient boundary repurposed as a convenient corner for newer divisions of land. The original entrance has been lost entirely, worn away or obscured beyond recovery.