An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
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The Caspian Sea is also classed as the world's largest lake.
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Check your map! Virginia extends farther west than West Virginia.
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Every person in the world can fit in Texas and be given over 1000 sq ft in which to live.
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The North Atlantic gets 2.5 centimetres (1in) wider every year.
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In one day, a full grown redwood tree expels more than 2 tons of water through its leaves.
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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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