What makes it quietly awkward, historically speaking, is that nobody is entirely sure what it is or when it was built. It could be a relatively mundane sheep pen from the nineteenth century. It could be something considerably older.

The structure is defined by a continuous earthen bank, roughly two metres wide at its base and narrowing to under a metre at the crest, with shallow ditches, known as fosses, running along both its inner and outer edges. These fosses are modest in depth, barely more than ten to fifteen centimetres, which gives the whole thing a low, unassuming profile in the landscape. The critical clue, or rather the critical absence of one, comes from cartographic evidence. The first edition Ordnance Survey six-inch map, surveyed in 1839, makes no mention of the enclosure at all. It only appears on the 1900 revision, where it is drawn as a continuous circular line rather than with hachures, the fine radiating marks that surveyors typically used to indicate earthen banks and raised features. That representational choice on the map suggests the cartographer may have understood it as a standing enclosure of some kind, possibly a functional pen, rather than an ancient monument. The post-1800 date implied by its absence from the earlier map would be consistent with a sheep enclosure built during a period of upland pastoral farming. And yet the very fact of its circularity keeps the question open. Circular enclosures in Ireland have deep prehistoric and early medieval roots, and a later farmer building a pen might just as easily have chosen a square or rectangular form.