1. In 1858, the first major earthquake was recorded in San Francisco, with a magnitude of 7.0. It caused significant damage to buildings and infrastructure throughout the city.

2. In 1909, filmmaker D.W. Griffith debuted his first film, "Rescued from an Eagle's Nest," which was shot entirely on location in the foothills of Northern California.

3. In 1928, the Sierra Club officially recognized April 10 as John Muir Day, in honor of the influential naturalist who was instrumental in the establishment of Yosemite National Park and other conservation efforts.

4. In 2010, a massive oil spill occurred off the coast of Santa Barbara, California, when an oil rig owned by BP exploded, leaking over 200 million gallons of oil into the ocean. The spill had devastating effects on local marine life and ecosystems.

5. In 2018, the California State Assembly voted to officially declare April 10 as Dolores Huerta Day, in honor of the civil rights activist and labor leader who co-founded the United Farm Workers union with Cesar Chavez. Huerta has spent decades advocating for workers' rights, women's rights, and environmental justice.