The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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The Dallas/Ft. Worth airport is larger than New York City's Manhattan Island.
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10 of the tributaries flowing into the Amazon river are as big as the Mississippi river.
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The 'King Ranch' in Texas is bigger than the state of Rhode Island.
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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.
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Check your map! Virginia extends farther west than West Virginia.
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