A ringfort, the circular earthen or stone enclosure that served early medieval Irish farming families as a defended homestead, once occupied a roughly thirty-metre diameter plot here. It was recorded on the first edition of the Ordnance Survey six-inch map, which places its existence firmly in the landscape as it was documented in the nineteenth century. Today, no visible surface trace survives.

The fact that it appears on that early OS map is itself the most concrete thing known about it. Surveyors moving through Connacht in the nineteenth century noted a circular enclosure and marked it accordingly, giving the site its only firm historical anchor. What erased it since then, whether agricultural clearance, land improvement, or simple time and pressure, is unrecorded. The townland of Annaghkeen is not without other ancient company, however. Several cairns, the term for mounded stone structures associated variously with burial or boundary marking, are recorded in the same area, suggesting this particular hillslope carried significance across a long stretch of prehistory and early history, even if much of that significance has been quietly swallowed by the ground.