But an aerial photograph taken in July 1989 revealed something invisible from the ground: a cropmark tracing the outline of a subrectangular enclosure, roughly 40 metres east to west and 50 metres north to south. Cropmarks appear when buried ditches or banks cause the vegetation above them to grow differently, often showing as darker or lighter stripes in a dry summer, and they can betray the presence of structures that have left no surface trace whatsoever.

The enclosure's fosse, a defensive or boundary ditch, is clearly visible on the western, northern, and parts of the eastern and southern sides, though the latter two become indistinct in the photograph. What makes the site particularly layered is the suggestion that it overlays the northern edge of a separate circular enclosure nearby, implying that at least two distinct phases or types of activity occurred in this spot. A possible bank alongside the fosse and the trace of a second, outer ditch along the northern and part of the eastern sides hint at something more substantial than a simple field boundary, perhaps a settlement that was enclosed, modified, and then enclosed again. Modern field fences now run immediately outside the western fosse and cut east to west across the northern half of the site, meaning the contemporary agricultural landscape sits almost directly on top of the ancient one, neither erasing it nor revealing it to anyone simply passing through.