The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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The average ice berg weighs 20,000,000 tons!
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Connecticut and Rhode Island never ratified the 18th Amendment (Prohibition).
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More than a dozen men have stood on the surface of the moon, but only three have been to Challenger Deep in the Marianas Trench, the deepest known spot in the ocean.
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Mexico City is built on top of an underground resevoir!
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The Niagara Falls moves upstream at an average rate of about 295ft a century!
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