The Bolivian city of Potosí was founded after vast deposits of silver were discovered in the mountains nearby.
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Shenzhen became the first Chinese city to ban eating cats and dogs.
The Royal Canadian Air Force was formed out of the Canadian Air Force.
Jesus Christ's Last Supper was held.
NASA celebrated April Fool's Day by telling the world that they found water on Mars.
The US Air Force accidentally bombed the Swiss city of Schaffhausen.