In a bend of a small eastward-flowing stream near Coolroe in County Kildare, there is a site that exists almost entirely as an absence. No earthwork rises from the surrounding tillage, no ditch is visible underfoot, and nothing in the landscape signals that anything of note ever stood here. The only evidence of the place comes from a single aerial photograph taken in 1970, in which the parched ground betrayed what lay beneath: a cropmark outlining a rectangular enclosure, roughly 50 metres on its longer axis and 30 metres on its shorter, defined by the ghost of a broad fosse.

A fosse is simply a ditch, typically dug to define or defend an enclosed space, and its former presence here has led archaeologists to classify the site as a possible moated site. Moated sites, which are found across Ireland but are particularly associated with areas of medieval Anglo-Norman settlement, were enclosed farmsteads or manorial centres surrounded by a water-filled ditch. They date mainly to the thirteenth and fourteenth centuries, and their rectangular plan, of the kind suggested by the Coolroe cropmark, is characteristic of the type. The location beside a stream bend would have made the management of water in such a fosse relatively practical. Beyond the cropmark itself, however, no surface trace survives, and the field has long since returned to level ground.