The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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Australia's Great Barrier Reef is 1,250 miles long!
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The Atlantic Ocean is saltier than the Pacific Ocean.
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An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
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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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The water between India and Sri Lanka is only 3-30 feet deep and was purportedly passable on foot until 1480 AD when a cyclone moved some sand around.
1
One cubic mile of seawater contains about 50 pounds of gold.
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The state of Florida is bigger than England!
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