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The World's Longest Underwater Cave Is Even Longer Than We Realized

The longest known underwater cave in the world is even longer than we thought. As of the start of this year, cave divers have ...

This Is the Deepest Freshwater Cave System in the U.S.—and You Can See Real Mermaids There

Weeki Wachee Springs State Park in Florida has enchanted visitors since 1947 with underwater performances by "real" mermaids.