Hachuring on these maps typically signals an earthwork of some antiquity, the kind of mark that draws archaeologists and curious walkers alike. The feature looks, at a glance, like one of the many low mounds scattered across the Irish landscape that might conceal a burial, a souterrain, or the remains of an ancient enclosure.

The reality is considerably more mundane, and perhaps more interesting for that. The mound is a rectangular heap of sand and gravel, roughly 21 metres long, just over 2 metres wide, and less than 2 metres high. Local knowledge holds that it is simply leftover construction material, the surplus brought in around the time the Villa Marina Constabulary Barracks was built approximately 80 metres to the north. The Royal Irish Constabulary built and occupied barracks across the country throughout the nineteenth and early twentieth centuries, and modest infrastructure works of that kind routinely left traces on the surrounding land. Nobody tidied this particular heap away, and when the cartographers arrived it was substantial enough to warrant a mark on the map, indistinguishable in notation from far older earthworks nearby. The flat, level landscape around Ballyvelaghan offered nowhere for it to disappear into.