14. Elk River, Minnesota
Known for good fishing and a lot of snow, this small city north of Minneapolis is not a remarkable place. Except since the 1990s, its residents have seen lots of very strange things flying through their skies. Witnesses have reported UFOs that look like cigars, wings, and large Vs. One object was said to be the size of a passenger jet; another was a disc ringed with multicolored porthole lights. Weirdest of all: a UFO spotted in 2008 shaped like a jellyfish.