On a south-east-facing slope near Sporthouse in County Waterford, a gentle hollow in the ground holds a quiet kind of ambiguity. To most eyes it reads as little more than a grassy depression, but its almost perfectly circular form, roughly 25 metres across and sinking between half a metre and a metre below the surrounding surface, suggests something far more deliberate than a trick of the terrain.

When the Ordnance Survey produced its six-inch map series in 1840, the feature was recorded as a circular embanked enclosure with an external diameter of around 35 metres. Embanked enclosures of this kind are broadly understood as enclosed areas defined by a raised earthen bank, and they appear across Ireland in a variety of forms and periods, some associated with settlement, some with ritual or ceremonial use, and many remaining stubbornly difficult to date without excavation. The discrepancy between the outer measurement recorded in 1840 and the inner dished area visible today likely reflects the degree to which the enclosing bank has weathered and spread over the intervening centuries, its material gradually slumping inward and softening the boundary between bank and interior. What survives is the dished centre, grass-covered and legible, if only just.