The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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Forest fires move faster uphill than downhill.
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Due to gravitational effects, you weigh slightly less when the moon is directly overhead.
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The Niagara Falls moves upstream at an average rate of about 295ft a century!
48
Europe is the only continent without a desert.
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There's a lake under Antarctica that is 25 million years old called Lake Vostok.
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