In the northwest corner of a pasture field in Monereagh, County Sligo, a small circular structure roughly five metres across was recorded on the Ordnance Survey six-inch map of 1837 under the name Faghtamonaghaun. By the 1913 revision of the same map, the label had acquired the parenthetical note "in Ruins". Today, there is no visible trace at ground level.

What makes this site genuinely curious is the uncertainty that surrounds its very nature. The name Faghtamonaghaun does not appear on either map edition in the distinctive antiquarian typeface that cartographers of the period used to signal a recognised antiquity, a convention that would normally indicate a ringfort, burial mound, or similar ancient feature. This means the surveyors themselves were not classifying it alongside scheduled monuments. Local memory, recorded from the first half of the twentieth century, recalled a small grass-covered earthen rise on the spot, which is consistent with a low earthwork of some kind, but nothing more specific was preserved. Whether the structure was a modest field enclosure, a collapsed building, or something older entirely, the record does not say. Farm buildings and a farmyard lie immediately to the west, and the surrounding ground is described as rough, the sort of marginal land where low earthworks can persist unnoticed for generations before finally disappearing.