https://motherboard.vice.com/en_us/article/594byq/where-the-devils-kettle-waterfall-to-nowhere-really-goes > On the Brule River in Minnesota’s Judge C. R. Magney State Park, an unusual waterfall has sparked imaginations for decades. That’s because this waterfall, called the Devil’s Kettle, splits into two: one half of the river flows up to the edge of the falls and tumbles over, but the other half slips into a hole at the top of the falls and disappears. > Recently, scientists were able to solve the mystery of the disappearing side using a simple stream-gauging technique. It turns out, the water doesn’t disappear at all.