Roughly forty metres across and slightly dished at its centre, it is the kind of feature that could pass unremarked, a shallow depression in the landscape that might read as nothing more than a trick of the terrain. What gives it away, at least to those who know to look, is its shape: a near-perfect ring, legible enough that the surveyors who produced the first Ordnance Survey six-inch map in 1838 recorded it clearly as a circular enclosure.

Enclosures of this kind are among the most common yet least understood monuments in the Irish countryside. The term covers a broad range of structures, from the substantial ringforts of the early medieval period, which typically served as enclosed farmsteads, to boundaries of uncertain date whose original purpose remains unclear. The slightly dished interior at Graigue suggests the ground within the enclosure has settled or eroded over time, hinting at long abandonment, though without excavation it is impossible to say with confidence when the enclosure was made or what it was made for. The 1838 mapping is the earliest firm documentation of the site, which means the feature was already old enough, and prominent enough, to attract the attention of the Ordnance Survey's field teams as they worked their way across Wicklow in the 1830s.