The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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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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The Amazon rainforest produces more than 20% the world's oxygen supply.
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The Niagara Falls moves upstream at an average rate of about 295ft a century!
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The Caspian Sea is also classed as the world's largest lake.
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In 1850, only 8% of the people in California were women.
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The city of Houston, Texas is built on a swamp and is slowly sinking!
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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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