A rath, as these circular earthwork enclosures are known in Irish, was typically built during the early medieval period as a defended farmstead, its banks and ditches marking both a boundary and a statement of social standing. This one was large enough to appear on Ordnance Survey maps more than a century and a half ago, and it held its shape in the landscape long enough to be photographed from the air. Then, sometime in the three years between 1974 and 1977, it was levelled.

The enclosure is marked clearly on the Ordnance Survey maps of 1841 to 1842 and again on those of 1916, meaning it persisted as a visible earthwork through at least seven decades of the twentieth century. Aerial photographs taken by the Geological Survey of Ireland in 1974 still show it as a defined feature. By 1977, however, a follow-up set of aerial photographs tells a different story: the banks are gone, and what remains is only a crop mark, the faint shadow that buried or disturbed archaeology casts on growing vegetation when seen from above. Crop marks form because soil that has been filled, churned, or compressed retains moisture and nutrients differently from the surrounding ground, causing crops directly above to grow at a slightly different rate or colour. It is one of the quieter ironies of Irish archaeology that features which survived a thousand years in the ground can vanish within a single generation, and yet still leave this ghostly trace for those who know how to look.