An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
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Mexico City is built on top of an underground resevoir!
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Even Antarctica has an area code. It's 672.
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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.
17
There are approximately three chickens for every human on Earth.
13
The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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