It is the kind of feature that reads as almost nothing from a distance, a slight thickening of the ground, a modest ridge, yet it belongs to a much larger system of boundary-making that stretches for kilometres in either direction.

The surviving section runs roughly north-west to south-east for about 700 metres, with a gap of approximately 100 metres where a small lake sits across its path. In cross-section it follows the classic form of a linear earthwork: a central fosse, which is a cut ditch, here roughly 2.4 metres wide and 0.35 metres deep, with an earthen bank thrown up on each side. The north-eastern bank is the larger of the two, around 4 metres wide and just over half a metre high, while the south-western bank is slightly more modest. The whole thing sits in a gentle basin, the surrounding land rolling softly around it, and it extends almost to the edge of another small lake of about 70 metres across. This is not an isolated feature. The earthwork connects to further sections, one continuing roughly 500 metres to the east-south-east, another extending some 2.6 kilometres to the north-west, suggesting a substantial territorial or land-management boundary of considerable age. Linear earthworks of this kind are found across Ireland, typically associated with early medieval or prehistoric divisions of land, used to demarcate grazing territories, tribal boundaries, or routes through the countryside. Who laid this one out, and exactly when, remains unrecorded.