1. California became a state: On April 30, 1850, California officially became the 31st state in the United States. Following the discovery of gold in 1848, California's population exploded, and its entrance into the Union was significant for its economy and demographics.

2. The Watts Towers were completed: On April 30, 1954, artist Simon Rodia completed the Watts Towers, a complex of 17 interconnected steel sculptures adorned with ceramics, glass, and other found objects. The towers are now a National Historic Landmark and an iconic piece of Los Angeles art.

3. Hungarian Freedom Fighters Day: On April 30, California celebrates Hungarian Freedom Fighters Day to honor the brave Hungarians who fought for their country's liberation during the 1956 Hungarian Revolution. Los Angeles is home to one of the largest Hungarian-American communities in the United States.

4. America's first automobile race: On April 30, 1895, America's first automobile race was held from Chicago to Evanston, Illinois. While not specific to California, this race was a significant milestone for the automobile industry and foreshadowed the car culture that would take hold in California in the following decades.

5. University of California established: On April 30, 1868, Governor Henry H. Haight signed the Organic Act that established the University of California. Today, the University of California system is a world-renowned institution with ten campuses across the state.