No historic map marks it. It appears on no official cadastral survey. Its existence came to light not through fieldwork or archival discovery but through the patient scrutiny of satellite imagery, the kind of quiet detective work that has been reshaping Irish archaeology in recent years.

The feature sits approximately 170 metres west of the townland boundary with Ballygillane, in the barony of Coshlea. What the aerial images reveal is a roughly circular area around 47 metres in diameter, its outline traced in part by a fosse, which is essentially a ditch dug to define or defend an enclosed area, running from the north-west around to the south-west. Where the fosse is absent, an existing field boundary appears to follow or incorporate the same line. That combination of a surviving ditch and a repurposed boundary is a common signature of earthworks that have been partially absorbed into the working landscape over centuries. Roughly 100 metres to the east lies a recorded ringfort, a type of enclosed farmstead typical of early medieval Ireland, which raises the possibility that the two features were part of the same broader settlement pattern, though no excavation has established any connection between them. The earthwork was compiled by Martin Fitzpatrick and uploaded to the record in August 2021.

Because this feature is not marked on any Ordnance Survey map, historic or modern, finding it requires cross-referencing the townland boundary between Kilmihil and Ballygillane and working westward across the pasture. The fosse section is the most legible part of the earthwork and is most likely to be visible at ground level as a slight depression, particularly after rain or in low winter light when shadows sharpen subtle changes in the terrain. The field has been reclaimed, meaning drainage and agricultural improvement will have reduced whatever relief once existed. A visitor arriving with a printed satellite image or a georeferenced mapping app will be better placed than one relying on instinct alone. The recorded ringfort to the east provides a useful orientation point.