The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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The Caspian Sea is also classed as the world's largest lake.
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Check your map! The Pacific entrance of the Panama Canal is farther East than the Atlantic entrance.
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The warmest temperature ever recorded on Antarctica was 3 degrees F.
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Every year, Alaska has about 5,000 earthquakes.
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An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
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There's a lake under Antarctica that is 25 million years old called Lake Vostok.
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The Sahara desert expands at about 1km per month.
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