1. The first recorded discovery of gold in California took place on February 18, 1848, when James W. Marshall discovered gold flakes in the tailrace of a sawmill he was building for John Sutter in Coloma. This discovery triggered the California Gold Rush.

2. On February 18, 1930, Pluto was discovered by astronomer Clyde Tombaugh at the Lowell Observatory in Flagstaff, Arizona. Pluto was later demoted to a "dwarf planet" in 2006, but its discovery remains an important achievement in the field of astronomy.

3. On February 18, 1952, a massive storm hit Northern California, causing widespread flooding and landslides. The storm caused over $20 million in damages and led to the construction of a network of dams, levees, and flood control channels to prevent future flooding.

4. In 1965, on February 18, the iconic Watts Towers in Los Angeles were designated as a National Historic Landmark. The towers, built by Italian immigrant Simon Rodia over a period of 33 years, are made of steel, concrete, and found objects and are a testament to the creativity and perseverance of their creator.

5. On February 18, 2001, Dale Earnhardt, a legendary NASCAR driver, died in a crash during the final lap of the Daytona 500 race in Florida. Although not a California-specific event, Earnhardt was popular among racing fans in California and his death had a significant impact on NASCAR and the sport of auto racing.