It measures roughly 34 metres east to west and 26 metres north to south, and its boundary is not a wall or a fence but an earthen bank, steep-sided and overgrown, between three and five metres wide and still standing about 0.6 metres high. Just outside the bank, a band of waterlogged ground thick with lush vegetation hints at a fosse, the shallow ditch that would originally have accompanied the bank and helped define the enclosure's edge.

This kind of embanked enclosure is a familiar, if often unexamined, feature of the Irish countryside. Such earthworks are generally associated with early medieval settlement, though without excavation it is rarely possible to assign a firm date or function. They may have served as enclosures for a farmstead, a place of assembly, or some form of enclosed ground related to land management or ceremony. The example at Cornagher is documented in Michael J. Moore's Archaeological Inventory of County Leitrim, published by the Stationery Office in Dublin in 2003, which catalogued dozens of such features across a county not always well represented in popular accounts of Irish archaeology. The interior is now grass and rush-covered, the bank softened by centuries of growth, and two modern entrances, each about four metres wide, have been opened at the north-east and north-west, presumably for agricultural access.

What makes this site quietly worth attention is precisely its ordinariness. It has not been excavated, restored, or interpreted. The fosse is legible only as a strip of wetter, greener vegetation. The bank is low enough to step over. It sits on a hillside in Leitrim doing nothing in particular, which is, in its own way, a reasonably honest account of how most early medieval enclosures have come down to us.