The monument is a ring-ditch, a term used for the circular trench that typically surrounded a prehistoric burial mound, and it survives here not as an earthwork but as a cropmark, a phenomenon that occurs when buried ditches retain more moisture than the surrounding soil, causing the vegetation above them to grow differently and reveal their outlines in aerial photographs. The circle in question is modest, roughly ten metres in diameter, but its existence was only confirmed because of a single aerial photograph taken on 16 July 1971 under conditions that made the buried fosse legible through the growth of the crop above it.

That photograph, taken as part of the Cambridge University Collection of Aerial Photography, shows something else as well. A second ring-ditch lies approximately ninety metres to the south-south-east, and a possible enclosure appears to the south-east. More striking still is the presence of a relic field system in the same area, one that appears to be later in date than the ring-ditches themselves. The evidence for this sequencing is a field boundary running roughly north-west to south-east directly across the second ring-ditch, cutting through it in a way that suggests the field system was laid out after the ditches had already been buried and forgotten. It is a quiet but legible stratigraphy, the landscape overwriting itself over many centuries, each layer slightly obscuring the one beneath.