The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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Israel's Dead Sea is 1,312 feet below sea level.
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An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
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It takes a drop of ocean water more than 1,000 years to circulate around the world.
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The state with the longest coastline in the Continental U.S. is Michigan.
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Forest growth in the US has exceeded harvest since the 1940’s. Today, we have more trees than any time in the past 100 years.
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