In a flat tillage field in County Kildare, two concentric rings lie buried beneath the soil, invisible to anyone walking past but legible from the air as a ghost of something far older. The feature shows up as a cropmark, a phenomenon where buried ditches and banks alter the growth rate of crops above them, producing colour and texture differences that become visible in aerial photography, particularly during dry summers when stressed vegetation reveals the outlines of what lies beneath. What the imagery captured here is a ring-ditch, a type of monument generally associated with prehistoric funerary or ceremonial activity, consisting of one or more circular ditches that once enclosed a central area.

The site sits roughly 45 metres south-east of Rheban Moat, a recorded earthwork in the same townland of Castlereban. It was identified by Sam Hughes from Google Earth aerial imagery dated 19 July 2021. The cropmark shows two concentric fosses, that is, ditches, forming a double-ringed enclosure with an internal diameter of around 5 metres and an external diameter of around 15 metres. The relatively modest scale of the inner space is consistent with ring-ditches elsewhere in Ireland, which range from modest circular cuts around a single burial to larger ceremonial enclosures. Without excavation it is impossible to say what, if anything, lies at the centre, or when exactly the ditches were dug, but the form places it broadly within a tradition stretching from the Neolithic through the Bronze Age.