An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
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The Niagara Falls moves upstream at an average rate of about 295ft a century!
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The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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The Dallas/Ft. Worth airport is larger than New York City's Manhattan Island.
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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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There are more than 50,000 earthquakes throughout the world every year!
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The city of Houston, Texas is built on a swamp and is slowly sinking!
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The average ice berg weighs 20,000,000 tons!
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