At Sopwell in County Tipperary, a semi-circular earthwork once occupied the highest point of a tillage field, visible enough in 1840 for the Ordnance Survey cartographers to record it carefully on their six-inch map. Today, nothing can be seen at ground level. The feature has been ploughed or otherwise worked away to the point where the land gives no outward sign that anything was ever there.

The 1840 Ordnance Survey map shows the earthwork as a platform-type feature, semi-circular in shape, with a roadway running north to south cutting across its western side. Platform earthworks of this kind can take several forms in the Irish landscape, sometimes representing the levelled remains of a ringfort, a raised enclosure, or an older field boundary, though the specific origins of this particular feature are not recorded. What is clear is that it sat on elevated ground, the kind of position that would have made it conspicuous in an earlier agricultural landscape. By the time the Ordnance Survey returned to revise their maps, the earthwork had already disappeared from the record entirely, absent from every subsequent edition.

The roadway that once clipped its western edge may still exist in some form, but the earthwork itself survives only in that single early cartographic snapshot, a pencil-thin record of something that was already on its way out of the world when the surveyors passed through North Tipperary in the eighteen-thirties and forties.