Alta California was founded in 1769 by Gaspar de Portolá. Alta California had an area comprising the modern state of California and other states to the east. In 1822, Alta California became a territory in independent Mexico.

Alta is a small unincorporated community and census-designated place (CDP) in Placer County, California, United States, about northeast of Auburn. The village is located off Interstate 80 and along the historical First Transcontinental Railroad. The ZIP code is 95701 and the area code 530. One of the few buildings other than private residences is the Alta-Dutch Flat Grammar School serving kindergarten through eighth grade students. The high school that serves Alta is Colfax high School. Colfax High School is 11 miles southwest in the incorporated town of Colfax. The population of Alta was 610 at the 2010 census.