The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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There are more than 50,000 earthquakes throughout the world every year!
47
The Caspian Sea is also classed as the world's largest lake.
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The Dallas/Ft. Worth airport is larger than New York City's Manhattan Island.
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If Antarctica's ice sheets melted, the worlds oceans would rise by 60 to 65 metres (200 - 210ft) - everywhere
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Australia's Great Barrier Reef is 1,250 miles long!
45
In one day, a full grown redwood tree expels more than 2 tons of water through its leaves.
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