Venice Island was built on a foundation of tree trunks. 1200 years later, those same trunks still support almost all of central Venice.
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There are more than 50,000 earthquakes throughout the world every year!
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The Niagara Falls moves upstream at an average rate of about 295ft a century!
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The Amazon rainforest produces more than 20% the world's oxygen supply.
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The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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The average ice berg weighs 20,000,000 tons!
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One cubic mile of seawater contains about 50 pounds of gold.
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