11 places on Earth that are still unmapped
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This underwater cave system on Mexico’s Yucatán peninsula, thousands of kilometres long, has remained largely unexplored since the time of the Mayans, and doesn’t exist on any maps, according to photographer Klaus Thymann. He’s both begun to explore – a pursuit not without its dangers – and photograph it in order to bring about awareness that will lead to its conservation, he told The Guardian. The rivers that run through the system “form the aquifer of Yucatán and support about 11 different ecosystems”.