In a flat, working tillage field near Kilmoney in Co. Kildare, a circle roughly 25 metres across lies completely invisible to anyone walking past it. There is no mound, no hollow, no visible disturbance. The only way it reveals itself is from the air, where the soil and crop above an ancient buried ditch respond just slightly differently to stress and moisture, producing what archaeologists call a cropmark. In dry summers especially, the ring resolves into view: a narrow band of discolouration tracing a near-perfect circle, the ghost of a fosse, or enclosing ditch, that once defined a structure now entirely below the plough line.

The feature was reported by Jean-Charles Caillere and is visible on aerial imagery captured between 2013 and 2018. The fosse itself appears to have been relatively narrow, somewhere between one and a half and two and a half metres wide. Circular enclosures of this kind are broadly interpreted as ring-ditches, a term that covers a range of prehistoric monuments, from the surrounding ditches of ploughed-out burial mounds to the footprints of roundhouses or small enclosures. Without excavation it is impossible to say which category this particular feature falls into, but the form is consistent with Bronze Age funerary monuments found across the Irish midlands, where centuries of cultivation have gradually erased everything above ground while leaving the cut of the original ditch preserved in the subsoil below.