The Caspian Sea is also classed as the world's largest lake.
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It takes a drop of ocean water more than 1,000 years to circulate around the world.
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The Niagara Falls moves upstream at an average rate of about 295ft a century!
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The warmest temperature ever recorded on Antarctica was 3 degrees F.
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Every year, Alaska has about 5,000 earthquakes.
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A volcano has enough power to shoot ash as high as 50 km into the atmosphere.
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Australia's Great Barrier Reef is 1,250 miles long!
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