The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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The city of Houston, Texas is built on a swamp and is slowly sinking!
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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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One cubic mile of seawater contains about 50 pounds of gold.
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There's a lake under Antarctica that is 25 million years old called Lake Vostok.
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Check your map! Virginia extends farther west than West Virginia.
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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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