The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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The names of the continents all end with the same letter with which they start, excluding the North and South infront of AmericA.
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The Amazon rainforest produces more than 20% the world's oxygen supply.
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10 of the tributaries flowing into the Amazon river are as big as the Mississippi river.
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Mexico City is built on top of an underground resevoir!
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Check your map! The Pacific entrance of the Panama Canal is farther East than the Atlantic entrance.
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