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 longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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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.
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The Caspian Sea is also classed as the world's largest lake.
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Even Antarctica has an area code. It's 672.
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In one day, a full grown redwood tree expels more than 2 tons of water through its leaves.
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Australia's Great Barrier Reef is 1,250 miles long!
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Every year, Alaska has about 5,000 earthquakes.
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