Every year, Alaska has about 5,000 earthquakes.
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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.
17
Australia's Great Barrier Reef is 1,250 miles long!
45
The North Atlantic gets 2.5 centimetres (1in) wider every year.
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Venice Island was built on a foundation of tree trunks. 1200 years later, those same trunks still support almost all of central Venice.
8
The Caspian Sea is also classed as the world's largest lake.
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The Atlantic Ocean is saltier than the Pacific Ocean.
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The warmest temperature ever recorded on Antarctica was 3 degrees F.
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