Examples can be found world wide. Various hypotheses have been offered to explain their formation, ranging from the naturalistic to the paranormal. Naturalistic explanations include man-made hoaxes or geological anomalies, while paranormal explanations include formation by UFOs. Many circles are known to be man-made, such as those created by Doug Bower, Dave Chorley, and John Lundberg, and a 2000 study into circle hoaxing concluded that 80 percent of UK circles were definitely man-made... Bower and Chorley were awarded an igNobel Prize in 1992 for their crop circle hoaxing.

Are crop circles real? See for yourself!
This DVD shows and explains many crop circles all over the world. It also trys to uncover the mysteries behind the whole phenomenon