On a north-facing slope of gently rising grassland at Corbrack in County Westmeath, an earthwork is recorded that has entirely vanished from the surface. No bank, no ditch, no depression in the turf offers any hint that something once stood or was shaped here by human hands.

What makes the site more than a footnote is its appearance on William Larkin's 1808 map of County Westmeath. Larkin's survey is a significant document in Irish cartographic history, produced at a time when systematic county mapping was still far from routine, and the fact that he recorded an earthwork at this location suggests it was legible in the landscape at the turn of the nineteenth century. Earthworks as a category covers a broad range of constructed features, from enclosures and ring forts to field boundaries and burial mounds, and without surface evidence it is impossible now to say which kind once occupied this slope. At some point between Larkin's survey and the present day, whatever existed here was levelled, most likely through sustained agricultural activity, leaving only the map entry as evidence of its existence.