Unlike some types of paranormal activity, crop circles leave behind plenty of evidence to document. They've been widely photographed and studied from all possible angles. Nonetheless, their true origin remains a intriguing mystery. Although they are commonly believed to be a modern phenomenon, the circles are mentioned in texts back to the year 1678.
Crop circles are patterns found in fields, over tree-tops, and in ice and snow.
They're most often found in wheat or corn fields, but have been seen in fields of oat, canola and barley. Crop circles in England have gotten the most attention, but circles have been found in the United States, Canada, India, Czech Republic, Australia, the Netherlands, among other places. To-date approximately 9,000 have been reported and documented throughout the world, with England claiming the majority. Reports of crop circles in more recent times began in the 1970s. Two gentlemen, sitting on a slope near Warminster, England, witnessed a circle being formed in the moonlight.