The walls themselves are modest, no more than sixty centimetres thick and barely reaching forty centimetres in height at their tallest, yet they trace out a roughly rectangular area of around 180 metres by 160 metres. That they survive at all is down to the bog's unusual preservative qualities; as peat accumulated over centuries, it effectively buried and held in place walls that would otherwise have collapsed entirely or been robbed for later building.

What makes the arrangement particularly interesting is its character. The boundaries are mainly curvilinear rather than straight, following the natural logic of the terrain rather than any imposed geometric plan. Many of the stones are set at right angles to the line of the wall, a technique sometimes used to give a wall greater stability or to key it into the ground. Several gaps interrupt the walls, likely original openings that served as field entrances, though some may be the result of later disturbance. A related enclosure, a separate but associated structure, sits roughly seventy metres to the north-west, suggesting this was once part of a broader organised landscape. Relict field systems of this kind, sometimes called booley or pre-bog field systems depending on their date and use, are reminders that land in Ireland was being divided, managed, and farmed long before the patterns visible in today's countryside were ever established. The bog, in covering them, also kept them.