At Rathnamanagh in County Laois, a subcircular enclosure roughly 35 metres across was recorded on the Ordnance Survey six-inch map of 1841, yet today there is nothing visible at ground level. No earthwork, no ridge in a field, no trace that the eye can follow. The site survives only as a cartographic ghost, a shape committed to paper by surveyors who could still see something worth marking.

Enclosures of this kind are among the more common, and more ambiguous, features of the Irish archaeological landscape. The term covers a wide range of structures, from the circular ringforts that once served as enclosed farmsteads during the early medieval period, to prehistoric burial enclosures and ceremonial sites, to later agricultural boundaries. Without excavation, it is rarely possible to say with certainty what a given enclosure was built for or when. What the Rathnamanagh example tells us is its approximate shape and size, subcircular in plan with a maximum diameter of around 35 metres on a north-west to south-east axis, dimensions that would be consistent with a modest ringfort. That it appeared on the 1841 map suggests it retained some surface expression into the nineteenth century, most likely a low earthen bank or fosse, a ditch encircling the interior, that has since been levelled by agricultural activity or the simple passage of time.