1. On September 7, 1769, a Spanish expedition led by Gaspar de Portolá and Father Junipero Serra became the first Europeans to explore the San Francisco Bay. This marked the beginning of the Spanish colonization of California.

2. In 1851, California's first State Fair was held in San Francisco on September 7th. It was a three-day event that included exhibits of livestock, agriculture, and industry from all over the state.

3. September 7, 1936, marked the opening of the San Francisco-Oakland Bay Bridge, one of the world's longest suspension bridges at the time. The bridge connected San Francisco and Oakland, making transportation between the two cities more convenient.

4. On September 7, 1940, the historic La Cienega Boulevard restaurant, the Original Pantry Cafe, opened in Los Angeles. The diner has been open 24 hours a day, seven days a week since then and is famous for its huge portions of home-style meals.

5. In 1979, California Governor Jerry Brown signed a bill recognizing September 7th as California Admission Day, recognizing the state's admission to the Union on September 9, 1850. It is now an official state holiday.