Two circles were found at Wooburn Green in 1977, and by something of a coincidence were visited by Andrew Collins, who years later, would write and publish on the phenomenon.
They were first seen by Ken Phillips of the British UFO Research Association (BUFORA), whilst investigating reports of lights in the sky at Wooburn Green, near High Wycombe in Buckinghamshire. He made the discovery on May 30, at Windsor Hill, and intriguingly one of the circles was beneath a power line.
Shortly thereafter, Collins went back to the spot to carry out a site investigation. As a result, the dimensions of the circles were recorded, and they would seem to form a doublet rather than two separate events.
The circles are described in Collins' Book The Circlemakers (1992). A scale drawing is given below.
They are noted as being "perfectly circular", in green barley which was "swirled". Although they seem not have been flattened hard to the ground, they are otherwise typical of crop circles recorded elsewhere.
At the time they were dismissed as having a mundane cause. However the swirling rules out the farmer's suggestion that they were caused by buried rubbish affecting the soil above. It was
not until years later that Collins identified what they were.
Below: scale diagram. Collins describes the respective diameters as 16 yards and nine yards, 11 yards apart.