Many people believe crop circles are made by alien spacecraft, possibly as some type of communication or a means of marking a site for landing or for some other purpose.
I feel this is the most plausible explanation for crop circles.
There is just no earthly explanation that could explain how these giant shapes could be made so precisely, in the dark, in a matter of hours…..most leaving behind trace amounts microwave radiation.
If you want to hear more about Crop Circles, this is my favorite book:
2 bloke sin the field with abotte of cider, Im afraid
If not them, then who else?
Aliens and UFOs get my vote here.