This one in Killeenduff, County Sligo, earns its place by what is no longer there. A mound, once significant enough to be formally recorded, had by 2003 left no visible trace in the gently undulating pasture where it was supposed to stand.

The site has an odd administrative biography. It was absent from every edition of the Ordnance Survey six-inch maps, which were the standard tool for capturing earthworks and field monuments across Ireland from the mid-nineteenth century onward. It was also left out of the Sites and Monuments Record compiled in 1989. By 1995, however, it had been picked up and included in the Record of Monuments and Places, the statutory list that afforded legal protection to archaeological sites. That six-year gap between the two records suggests the mound came to official attention somewhere in between, only for an inspection in 2003 to find that small-scale quarrying of sand and gravel had disturbed the area, and that nothing of the mound itself remained to be seen. Whether it was always a modest feature, or whether it was substantially removed by the quarrying activity, the notes do not say.