American Canyon (previously known as Napa Junction) is a city located in southern Napa County, California, 35 miles (56 km) northeast of San Francisco in the San Francisco Bay Area. The 2010 census reported the city's population at 19,454. Its ZIP Code is 94503, and its area code is 707. It is in the Pacific Time time zone and observes Daylight-Saving Time. The city was incorporated in 1992.