The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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The average ice berg weighs 20,000,000 tons!
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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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Check your map! Virginia extends farther west than West Virginia.
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The water of the Antarctica is so cold that nothing can rot there.
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The Niagara Falls moves upstream at an average rate of about 295ft a century!
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The North Atlantic gets 2.5 centimetres (1in) wider every year.
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An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
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