Fontana () is a city in San Bernardino County, California. Founded by Azariel Blanchard Miller in 1913, it remained essentially rural until World War II, when entrepreneur Henry J. Kaiser built a large steel mill in the area. It is now a regional hub of the trucking industry, with the east-west Interstate 10 and State Route 210 crossing the city and Interstate 15 passing diagonally through its northwestern quadrant.
It is home to a renovated historic theater, a municipal park, and the Auto Club Speedway on the site of the Kaiser Steel Mill. Fontana also hosts the Fontana Days Half Marathon and 5K run. This race is the fastest half-marathon course in the world.
The United States Census Bureau estimated Fontana's 2019 population at 214,547, making it the second-most populous city in San Bernardino County and the 19th largest in the state. The name fontana is Italian for fountain or water source, being in close proximity to the Santa Ana River to the east.
Fontana was founded in 1919 by Azariel Blanchard Miller. Within a few years it became an agricultural town of citrus orchards, vineyards and chicken ranches and astride U.S. Route 66 (now known as Foothill Boulevard). The Fontana area was radically transformed during World War II when Henry J. Kaiser built the Kaiser Steel plant, at the time one of only two steel mills west of the Mississippi River outside the city limits.