California became the 31st state to join the United States of America.
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A shooting took place at YouTube's headquarters in San Bruno, California.
The Rutan Voyager became the first plane to fly around the world without stopping for fuel.
The first-ever message was sent from a ship to the shore at Cliff House, San Francisco.
The Avengers premiered in Los Angeles, California, US.
The Texas Chain Saw Massacre horror film premiered in cinemas in Los Angeles, California.