Somewhere beneath a flat tillage field in Co. Kildare, there is almost certainly a circular monument roughly thirty metres across. You would never know it from standing in the field. The ground is level, the crops grow evenly, and nothing breaks the surface to suggest that anything lies beneath. The only evidence comes from the air, and specifically from a single aerial photograph taken in 1973, in which the faint outline of a fosse, a defensive or enclosing ditch, traces a circular shape into the crop. What exactly it enclosed is uncertain. The site has been tentatively identified as either a ringditch or a ringbarrow, two forms of prehistoric funerary monument that share a broadly circular plan defined by a surrounding ditch, sometimes with an internal mound in the case of the barrow.

This particular enclosure is not an isolated curiosity. It sits within a dense cluster of levelled monuments detected across a roughly rectangular stretch of land approximately 650 metres east to west and 350 metres north to south, all of them known only from cropmarks gathered through multiple aerial surveys, including work by the Cambridge University Collection of Aerial Photographs and a survey conducted by Dr. Gillian Barrett. Cropmarks appear when buried features, ditches that retain moisture or the compacted remains of walls that shed it, affect how the vegetation above them grows. In a dry summer, the difference can become visible from altitude even when the ground itself shows nothing. The full cluster at Courttown includes outlying examples up to 250 metres to the south and 220 metres to the northwest, suggesting that whatever activity generated these monuments was spread across a meaningful area of this part of Kildare. No surface trace of any of them survives.