The field sits on a south-facing slope above the Awbeg River in north Cork, under tillage, with no earthwork, no hollow, no faint rise in the ground to suggest that anything ever stood there. Yet for well over a century, Ordnance Survey maps marked the spot clearly: a hachured circular enclosure, roughly fifty metres across on the 1842 and 1905 editions, shrunk slightly to around forty metres and ringed by a fosse on the 1937 revision. A fosse, in this context, is simply a defensive ditch dug around the outside of a ringfort's earthen bank. At some point between the mid-twentieth century and today, the site was levelled entirely.

What saved it from vanishing without record was a quarry. In 1973, archaeologist Dermot C. Twohig excavated this fort, designated Ringfort 3 in the project, alongside two neighbouring ringforts on the same threatened ground. At the time of excavation, the bank still stood to a height of 1.3 metres around most of its circumference, with a shallow external fosse and a causewayed entrance facing south-south-west. The causeway itself had been surfaced with gravel and cobbles, extending inward about six metres into the interior, though there was no evidence of a gate across the five-metre-wide opening. The bank proved to have been built in two distinct phases, suggesting the enclosure was modified or reinforced at some point after its initial construction. Inside, two separate sets of cultivation ridges were found, laid at different angles to one another. At the centre of the interior, a small rectangular arrangement of post-holes, seven metres by six, was interpreted not as a dwelling but as an animal pen; there were no hearths, no habitation debris, and no internal roof supports. A blue glass bead, a flint flake, and a whetstone were recovered from the vicinity. Beneath all of this, a linear trench predating the fort itself was also identified, hinting at activity on the slope before the ringfort was ever built.

Ringforts are among the most common archaeological monument types in Ireland, typically associated with early medieval farming settlements, but Lisduggan's example is unusual in how thoroughly it documents an agricultural rather than a domestic function. The absence of any sign of habitation inside, combined with the probable animal pen at the centre, complicates the standard picture of these enclosures as farmstead residences. Twohig's findings were published in 1990, and the site itself has long since returned to the ordinary surface of a working field.