Deep in the heart of the Amazon, legends tell of a river so hot that it boils from below. As a geoscientist, Andrés Ruzo's training told him the stories couldn't be true. But that was before he saw the river with his own eyes.
The river turned out to be no legend at all, but the sacred geothermal healing site of Mayantuyacu, nestled deep in the Peruvian rainforest. Up to 82 feet (25 meters) wide and 20 feet (six meters) deep, the river surges for nearly 4 miles at temperatures hot enough to brew tea. And a small portion of it is so hot that it actually boils.