The enclosure was already being absorbed into the working landscape by the time anyone thought to write it down properly, its banks repurposed as field divisions and its interior turned over to tillage. That process of quiet erasure is part of what makes it worth pausing over.

A ringfort, sometimes called a rath, was a roughly circular enclosure defined by an earthen bank and ditch, typically used as a defended farmstead during the early medieval period in Ireland. The Rossagh example was once a substantial one. Writing in 1910, a researcher named Jones recorded that it measured 85 yards in diameter and described it as a fine fort, noting that a portion had already been levelled to create a boundary between two farms. He also noted a well at the centre and the possible presence of a souterrain, an underground stone-lined passage often associated with ringforts and thought to have served for storage or as a place of refuge. The 1842 Ordnance Survey six-inch map still showed the site as a roughly circular enclosure, approximately 70 metres across, its arc running from the south-east to the north-north-west, with the eastern side already defined by a roadway and townland boundary. By the time the 1906 and 1937 editions were produced, that arc had been reclassified on the maps simply as a field boundary, the cartographic equivalent of the site being forgotten.

On the ground today, the evidence is subtle. The darker soil within the area of the former enclosure reflects the disturbed and organically rich ground that often marks where an earthwork once stood, and the slight depression near the interior likely corresponds to the well Jones described. The low scarp visible to the south-west is among the only above-ground traces of what was once, by any measure, a sizeable and well-appointed enclosure.