This internal subdivision is unusual for a rath, the term for a roughly circular earthwork enclosure of early medieval date, typically understood as a defended farmstead for a single household or extended family group. Whatever prompted someone to partition the interior here, the northern half of the enclosure is now waterlogged and marshy, which may reflect the original conditions as much as centuries of neglect.

The antiquarian Thomas Johnson Westropp visited the site in the early twentieth century and recorded it in 1913, identifying the townland as Tullagha and suggesting the fort may correspond to a place known in early Irish sources as Tulach Chuirc. He noted a rampart some thirty-one feet thick rising six feet above the interior ground surface, three gaps in the bank, and a waterlogged fosse, the ditch that runs around the outside of the enclosure. Later survey work confirmed and refined his observations. The rath is roughly circular, measuring approximately fifty metres across internally, with a steep-sided, flat-topped bank reaching three to four metres in height and ten metres wide at the base. Two of the entrances, one facing east and one to the south-south-east, are stone-lined and may be original features rather than later breaks. A third and fourth gap serve as narrow cattle passages, likely a much more recent addition to the working life of the enclosure. The site appears on Ordnance Survey six-inch maps from 1840 and again from 1916, named consistently, sitting on a gentle rise beside a stream in undulating rough pasture, with faint traces of earlier cultivation visible in the surrounding landscape.