The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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A waterfall known as The Devil's Kettle empties water into a hole and nobody knows where it ends up!
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Israel's Dead Sea is 1,312 feet below sea level.
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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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There are more than 50,000 earthquakes throughout the world every year!
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More than 25% of the world's forests are in Siberia.
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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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