A ringfort, or rath, once occupied a south-east facing slope with views across Lough Lene to the north and east, a position typical of how early medieval Irish farming families chose their ground: elevated enough for drainage and visibility, but sheltered from the prevailing weather. Today the earthwork has been levelled entirely, leaving no surface trace of what was once a defined enclosure roughly 32 metres across at its longest.

Ringforts are the most common archaeological monument type in Ireland, with tens of thousands recorded across the island. They functioned primarily as enclosed farmsteads during the early medieval period, roughly the fifth to twelfth centuries, with a bank and ditch encircling a family's living quarters, outbuildings, and livestock. The Ranaghan example measured approximately 32 metres north to south and 29 metres east to west, and its sub-circular outline was still clear enough to be mapped on the 1911 edition of the Ordnance Survey six-inch map. At some point between that survey and the present, the site was removed from the landscape altogether. A second ringfort survives around 200 metres to the south-west, which at least gives some sense of what this one would have looked like before it was lost.