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Unexplained natural phenomena can be hard to come by these days. Devil’s Kettle is one such mystery.

Located in the Judge C. R. Magney State Park in northern Minnesota, Devil’s Kettle is a split waterfall. One side flows onto Lake Superior while the other drops into a large pothole after which no one is quite sure where the water goes. Everything from ping-pong balls to GPS trackers has been put into the hole hoping to map the water, but despite these many efforts, the secrets of Devil’s Kettle remain unknown.

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