It survives only in interrupted sections, sometimes grass-covered, sometimes swallowed by coniferous forest. In places it is no more than a simple ditch with a field bank thrown up along one side. In other stretches it opens into a flat-bottomed fosse, a defensive ditch, up to four and a half metres wide, with ground rising a metre or more on the south-west side and a low bank running along the north-east. It is not dramatic, and it is not meant to be. What makes it quietly remarkable is what it belongs to.

This earthwork forms part of the Black Pig's Race, a name given to a discontinuous system of linear earthworks that runs across Ulster and its margins, thought to date from the late Iron Age, roughly the last few centuries before the early medieval period. The name comes from folklore, which attributed the long ditches to the rooting of a great supernatural pig. In reality, the earthworks are believed to have served as territorial boundaries or defensive barriers across the natural routeways and gaps in the drumlin belt that might otherwise have offered easy passage into Ulster from the south and west. The Corraleskin section sits close to the County River, which still marks the boundary between Leitrim and Fermanagh. To the north-west, the ditch terminates around 150 metres south-west of Lough Tiernan, where it connects, across a gap of some 400 metres, to a neighbouring section that continues the line of the earthwork towards Donegal Bay. A further section lies approximately 2.6 kilometres to the south-east. The north-western end of this particular ditch was at some point pressed into use as a roadway, which says something about how these old features are absorbed into the landscape over centuries rather than preserved in isolation.