1. In 1769, Spanish explorer Gaspar de Portolá and his party arrived in San Diego, becoming the first Europeans to land in California.

2. In 1846, the United States declared war against Mexico, which eventually led to California becoming a U.S. territory through the Treaty of Guadalupe Hidalgo.

3. In 1863, the Central Pacific Railroad began construction on the Transcontinental Railroad in Sacramento, California, which connected the East Coast to the West Coast.

4. In 1938, aviator Douglas "Wrong Way" Corrigan landed in Dublin, Ireland, after flying from New York to California, but was meant to fly to New York.

5. In 1955, Disneyland, the first Disney theme park, opened its doors in Anaheim, California, and became an instant hit, attracting millions of visitors from all over the world.