At Rathduff in Co. Westmeath, a prehistoric or early medieval enclosure once occupied a gentle rise on a north-west-facing slope, its oval outline visible enough in the nineteenth century to be carefully mapped. Today there is nothing left to see. What makes this site quietly compelling is not what it preserves but what it documents: the steady erasure of a feature that was already, by the time anyone thought to ask, long gone.

The Ordnance Survey's six-inch map of 1837 recorded the enclosure as an oval-shaped earthwork, roughly fifty metres along its north-east to south-west axis and about thirty-eight metres across, defined by a scarp, which is a steep natural or artificial slope forming one face of an earthen boundary, and by an external fosse, a shallow ditch running around the outside. Field boundaries radiated from it on three sides, suggesting it had been absorbed into the working landscape of the farm rather than left to stand apart. By the time the twenty-five-inch map was produced in 1913, the picture had shifted: the enclosure was now described through a bank running from south-west to north-east, with field boundaries extending beyond the monument itself, the distinction between ancient earthwork and modern field system becoming harder to draw. When the site was assessed in 1975, it was described simply as demolished. Aerial photography has since confirmed that no surface trace survives.