On a low rise in the corner of a field in Balrath, County Westmeath, there sits what was once a ringfort, the circular or roughly circular earthwork enclosures that served as farmsteads and defended homesteads across early medieval Ireland. Nothing of it can now be seen at ground level. The earthwork has been levelled entirely, leaving only its coordinates and a cartographic ghost.

That ghost survives in the 1837 edition of the Ordnance Survey six-inch map, which recorded the site as a D-shaped enclosure occupying the corner of a field where two townland boundaries converge. The eastern side of the enclosure was formed by the field fence running north to south, which also marks the boundary with the townland of Balrath East, while the southern side followed the fence running east to west along the boundary with the townland of Killynan, sometimes recorded as Killynan (Pratt). The ringfort, in other words, was already being absorbed into the working geometry of the landscape by the time the surveyors arrived, its edges conflated with the boundary lines of adjoining properties. Whether it had already been substantially reduced by then, or whether it disappeared in the decades following, the map is now the only record of its shape.