Somewhere beneath a tilled field in Kilmead, County Kildare, lies the ghost of a large circular enclosure, invisible at ground level but legible from the air as a faint cropmark tracing the line of a back-filled fosse. A fosse, in this context, is simply a ditch, one that was deliberately filled in at some point in the past, leaving no surface trace. What survives is purely a phenomenon of differential crop growth: the soil above a former ditch retains more moisture and nutrients, causing the plants above it to grow slightly differently from those around them, and from a sufficient height that contrast becomes a clear, readable line. In this case, the line describes a circle roughly 60 metres across.

The enclosure came to notice through aerial imagery, spotted on Bing Maps and brought to the attention of recorders by P. Reid. What the site once was, and when it was in use, is not recorded, though circular enclosed sites of this general type in Ireland range from prehistoric farming settlements to early medieval ringforts, the latter being the most common form of enclosed rural settlement in the Irish countryside between roughly the fifth and twelfth centuries. A second, smaller enclosure sits immediately to the north-west, suggesting the area preserves traces of more than one phase or episode of past occupation, each now reduced to faint signals in the soil beneath the crops.