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UNDERWATER RIVER!
Deep beneath: Mexico’s Yucatan Peninsula is a dive site like no other. Surrounded by fallen leaves and dead tree branches in that seems like a deep-sea mystical forest runs a surreal underground river 100 feet below the surface.
The strange natural phenomenon is said to be made possible by a thin layer of hydrogen sulfate, so that causes the freshwater above to separate from the saltwater below. The saltwater, which is more dense than the freshwater, can flow independently on the ocean floor, seeming an eerie cloud-like appearance.
This extraordinary dive site is turned up in Cenote Angelita, an advanced scuba diving cenote (a pit or sinkhole with water beneath) 10 to 15 minutes south of Tulum, Mexico.