In a field near Prumpelstown in County Kildare, something old and linear lies just below the surface, invisible to anyone walking the ground but legible from the air. Aerial photographs reveal cropmarks tracing the course of two parallel fosses, that is, ditches, which together suggest the boundaries of an ancient road or trackway. The crops growing above the buried ditches respond differently to the soil beneath them, producing faint but readable marks that outline what was once, in all likelihood, a managed route through the landscape.

The two fosses run broadly east to west, curving gently southward before straightening again, and remain traceable for approximately 300 metres. Roads of this kind, flanked by drainage ditches to keep the surface passable, are known from various periods of Irish prehistory and early history, and the double-fosse arrangement is a recognised feature of constructed trackways. Whether this one dates to the Bronze Age, the early medieval period, or some other era is not clear from what the photographs alone can tell us. What they do confirm is that Prumpelstown sits over a corridor of movement that somebody, at some point, thought worth the considerable effort of digging out and maintaining.