Ringfort (Rath), Ardline, Co. Sligo

A rath is an earthen ringfort, typically a raised circular bank enclosing a farmstead or dwelling, and they were built in their thousands across Ireland during the early medieval period. This one, however, has become more of a cartographic ghost than a physical presence.

When the Ordnance Survey recorded the area at the six-inch scale in 1838, the site appeared as an embanked circular enclosure roughly thirty metres in diameter, sitting close to the crest of its drumlin, a smooth elongated hill formed by glacial action. By the time surveyors returned for the revised six-inch map of 1914, almost nothing remained. The only trace noted was a curving field boundary running from north-north-east to south-east, possibly preserving part of the original bank in the line of a later land division. Between those two surveys, the enclosure had been absorbed into the agricultural landscape so thoroughly that it is now described as not visible at ground level at all.