Half a metre thick and roughly thirty centimetres high where it clears the ground, it runs south-westward for about twenty-five metres before disappearing beneath the peat, then re-emerges intermittently across a further fifty metres before curving away to the south-east. It is not dramatic to look at, but that partial submersion is the point: the bog has been slowly consuming this boundary for long enough that the wall and the landscape it once organised are now only partly legible.

What survives at Coolnagoppoge is the outline of an agricultural system that has otherwise vanished. To the north of the wall, faint cultivation ridges, each around 3.2 metres wide, are still just visible. These are the kind of lazy-bed or ridge-and-furrow workings associated with small-scale tillage on marginal ground, coaxing crops from soil that was never especially cooperative. The curvilinear form of the wall itself is significant: straight boundaries tend to reflect later, more systematic land reorganisation, while curved or irregular enclosures often suggest earlier, more organic patterns of land use, shaped by the terrain rather than imposed upon it. Close by, to the north-east, sits a rath, a roughly circular earthen or stone enclosure of the early medieval period typically associated with a farmstead. The proximity of the field boundary to the rath raises the quiet possibility that both belong to the same working landscape, the wall parcelling out the ground that someone, long ago, was farming from inside that enclosure.