In this underwater photo taken Aug. 21, 2015, in the flooded Hranicka Abyss, Czech Republic, Polish explorer Krzysztof Starnawski is seen examining the limestone crevasse and preparing for a 2016 ... more 
In this underwater photo taken Aug. 21, 2015, in the flooded Hranicka Abyss, Czech Republic, Polish explorer Krzysztof Starnawski is seen examining the limestone crevasse and preparing for a 2016 expedition to measure it depths. On Sept. 27, 2016 Starnawski and his Polish-Czech team discovered that the cave goes 404 meters (1,325 feet) down, making it the world's deepest known flooded abyss. (Krzysztof Starnawski of the Krzysztof Starnawski EXPEDITION via AP) less 
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Associated Press
Fri, Sep 30, 2016 10:09 AM EDT