It measures roughly 94 metres on its longer axis and 67 metres across, a substantial enclosure by any reckoning, and yet it sits so low and so merged with the fields around it that it could easily pass for nothing more than a slightly irregular arrangement of hedgerows and ditches.

The enclosure is defined by a fosse, a defensive ditch, now silted up to a width of about 1.4 metres, and an external earthen bank that still stands 1.2 metres high and runs to around 3 metres wide. A fosse of this kind would originally have been considerably deeper and more formidable; what remains is the softened, waterlogged remnant of something that once presented a meaningful boundary. Along the eastern, southern, and western sides, later field walls have been laid directly on top of the bank, so that the older earthwork has been quietly pressed into service as a foundation for more recent agriculture. A gap of about 6.5 metres at the north-east corner looks modern, but may well preserve the position of the original entrance. Inside, the flat interior has been divided into three sections by further field walls, so that later farming has effectively colonised the space without quite erasing the outline that was there before.

The relationship with Cloonboo Castle nearby invites speculation, though the precise chronological connection between the two structures is not established. What is clear is that the enclosure belongs to a type of earthwork, defined by bank and fosse, that was used across medieval Ireland to demarcate territory, protect settlement, or define the grounds associated with a fortified site. Here, the marshy setting would have added a natural defensive dimension, with wet ground doing some of the work that the earthworks alone could not.