At Castlewaller in County Tipperary, a circular enclosure was recorded on the first edition Ordnance Survey six-inch map, shown sitting within a grove of trees, the kind of detail that nineteenth-century surveyors noted carefully and that later generations have struggled to verify. Today, no surface remains are visible at the location. Whatever once stood or was bounded there has left no trace that can be seen at ground level.

The first edition Ordnance Survey six-inch maps, produced in Ireland from the 1830s onwards, captured the landscape at a moment before agricultural intensification, land clearance, and drainage reshaped so much of it. Circular enclosures of the kind marked at Castlewaller are typically associated with early medieval settlement, the remains of a rath or ringfort, an earthen or sometimes stone-built enclosure that would have enclosed a farmstead. They were once enormously common across Ireland, numbering in the tens of thousands. Many have since been levelled by ploughing or removed by land improvement schemes, surviving only as crop marks, slight ground undulations, or, as here, as ink on an old map. The grove of trees noted by the original surveyors may itself have been a clue to the enclosure's former presence, since such features were often left unploughed out of custom or superstition, their associated vegetation outlasting the earthworks themselves.

What remains at Castlewaller now is essentially an absence, a place where the map and the ground no longer agree. That disagreement is itself a kind of record.