These strange formations found in fields across the world have been widely reported since the 1970s and into present day.
Characterized by elaborate circular patterns of flattened wheat, barley or other crops -- many conspiracy theorists think these designs are not man-made, but formed by something out of this world, such as aliens trying to communicate with us or other mystical powers.
This Bavarian farmer's field is the latest pattern to make international headlines. The rings were discovered by a balloonist and have drawn thousands of enthusiasts who have arrived to sing, dance or just stand in the circle.
Most crop circles are believed to be man-made. The process usually involves using a wood plank and ropes designed to lay down crops with each step. This method was made popular by Doug Bower and Dave Chorley in 1991 when they claimed to have made most crop circles that have appeared in England since the late 70s.
Other theories as to the cause of crop circles range from swirling winds or aircraft that flatten the crops to electromagnetic radiation that forms the patterns. Scientists have reported stronger magnetic fields within crop circles and some people say that they experience a prickling sensation while standing within them.
Many crop circles appear near roads, populated areas and even historical sites like Stonehenge, which leads people to believe most are created by man. However, many crop circle enthusiasts and researchers still maintain they are made by forces beyond our understanding.
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