Tucked away in Russia’s Nizhny Novgorod region is the otherworldly Vad Lake. For hundreds of years the lake, which is about 325 miles east of Moscow, was fed by two springs. One of the springs has collapsed, creating an immense sinkhole more than 150 feet down. The pressure of water from the remaining spring is so strong that it creates a convex lens above the surface of the lake. In the summer, this surface layer can be warm and murky, but a 33-foot descent reveals water so transparent, it seems as if you’re flying over land. To increase this sensation, I gave the diver brightly colored balloons to carry as he hovered above the blanket of green algae.
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