The ground gives nothing away; no earthwork, no raised lip, no hollow where a bank once stood. What survives is a cartographic ghost, an oval outline preserved on the Ordnance Survey six-inch maps, oriented roughly north to south and measuring approximately 45 metres across.

A rath, in Irish archaeological terms, is an enclosed farmstead of the early medieval period, typically defined by one or more earthen banks and ditches and used as a residence by a farming family of some social standing. The Carrownaseer example was documented by Neary in 1914, who classified it as a circular earthen rath and noted a feature he described as a gangway at the eastern side, likely the original entrance causeway crossing the enclosing ditch. Locally, the site was known as Mc Walter's Rath, a name that attaches a personal identity, however faint, to what is otherwise an entirely anonymous piece of ground. Who Mc Walter was, and when that association formed, is not recorded.

The complete absence of visible surface trace is a reminder of how thoroughly agriculture and time can erase even substantial earthworks. The banks and ditches of a rath could originally stand several metres high, yet centuries of ploughing, grazing, and drainage work leave nothing that a casual eye would notice. The six-inch Ordnance Survey maps, produced in Ireland during the 1830s, captured many such enclosures at a moment when some trace still remained or local memory was still sharp enough to guide the surveyors. In this case, that cartographic record is now the only reliable evidence that anything was ever there at all.