Ring-ditch

The term used to describe a circular ditched feature, often a round barrow that has been ploughed out until all that remains is the outer ditch. Ring ditches are often seen as crop marks because the ditches have become filled over time. There are many ring-ditches known from aerial photographs in Buckinghamshire. Although many have been found on the river gravels of the Thames, Colne and Great Ouse, such as the recent discoveries at Sentry Hill, Marlow, some have been found on the clays of the north, such as two near Tingewick Airfield.