An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
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Check your map! Virginia extends farther west than West Virginia.
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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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Due to gravitational effects, you weigh slightly less when the moon is directly overhead.
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The Caspian Sea is also classed as the world's largest lake.
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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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Venice Island was built on a foundation of tree trunks. 1200 years later, those same trunks still support almost all of central Venice.
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