This one is notable for what no longer does. On the east-facing slope of a ridge running roughly north-east to south-west in Tullykenny, County Monaghan, there was once an earthwork fort, the kind of raised, roughly circular enclosure found in their hundreds across the Irish countryside. By the year 2000 it had been removed entirely, leaving no visible trace in the field.

When surveyors recorded it in 1967, the fort appeared as a subcircular mound about 30 metres across at its longest, rising two and a half to three metres above the surrounding field and covered in grass and scrub. A scarp, the steep earthen edge that defines the boundary of such an enclosure, ran around its northern arc, with a berm, a flat shelf of ground sitting on top of the scarp, extending from the south-west round to the north. No original entrance could be identified, which is not unusual for earthworks of this type; many ring-forts and related monuments lost their formal gaps through centuries of agricultural reshaping. There was also a grass-covered quarry hole in the eastern portion of the mound, suggesting the site had already been partially disturbed before anyone thought to measure it. The monument was formally recorded in the Archaeological Inventory of County Monaghan published in 1986, but sometime between that documentation and around 2000 the earthwork was levelled altogether, most likely through agricultural clearance.

What makes Tullykenny worth pausing over is precisely this arc from record to erasure. The 1967 description preserves, in careful metric detail, something that now exists only on paper: a mound with a berm, a scarp, an unidentified entrance, and a quarry hole slowly greening over. The landscape holds no sign of any of it.