1. The first recorded earthquake in California occurred on May 16, 1812, in the San Juan Capistrano area.

2. On May 16, 1846, the United States declared war on Mexico, setting off the Mexican-American War, which would ultimately lead to California becoming part of the United States.

3. The first railroad in California, the Sacramento Valley Railroad, made its inaugural run from Sacramento to Folsom on May 16, 1856.

4. In 1934, construction began on the Golden Gate Bridge in San Francisco, which would ultimately become one of the most iconic landmarks in California history. May 16 marked the first day of construction on the south tower of the bridge.

5. On May 16, 1979, Elvira Arellano, a well-known activist for immigrant rights, was born in Michoacán, Mexico. Arellano became a central figure in the movement to grant legal status to undocumented immigrants and played a key role in advocating for the DREAM Act.