"The Devil's Kettle" might sound like a cheesy B-movie from the sixties, but it's actually a strange landmark located on the Brule River in Minnesota. At one point, the river splits into two different waterfalls; the first feeds into Lake Superior, but the second's destination is a little more mysterious.
Neither scientists nor nature enthusiasts can figure out where this second waterfall disappears to after it enters a nearby hole in the ground. Holes like this, referred to as "kettles," are located all around Minnesota and can often be traced easily. But when it comes to "The Devil's Kettle," no amount of tests can determine where all that water is going. While we highly doubt there are supernatural forces at work, it's fun to think about what sort of undiscovered geological phenomenon could be responsible for this bizarre landmark.