The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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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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The Amazon rainforest produces more than 20% the world's oxygen supply.
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The city of Houston, Texas is built on a swamp and is slowly sinking!
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Every person in the world can fit in Texas and be given over 1000 sq ft in which to live.
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Even Antarctica has an area code. It's 672.
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