Yucaipa ( yoo-KY-pə) is a city located 10 miles (16 km) east of San Bernardino, in San Bernardino County, California, United States. The population was 51,367 at the 2010 census, up from 41,207 at the 2000 census. According to San Bernardino County, the population in 2019 is 53,921. Yucaipa has the distinction of being the former longtime home to a large population of Serrano Indians and was also known for being the home base of what is now Stater Bros. Markets (founded in 1936, and now headquartered in San Bernardino). Yucaipa is located in the southwestern United States, in southern California, approximately 72 miles (116 km) east of Los Angeles. The city is approximately 2,600 ft (790 m) above sea level.
Yucaipa Valley supported a large population of Serrano Indians. The fertile valley was watered by springs and creeks running out of the San Bernardino Mountains. The Serrano lived in this location most of the year, but would make excursions into the mountains to gather acorns and other food items during their harvest season. The Serrano name for the area was Yucaipat which meant “green valley.” The Rancheria is marked by California Historical Landmark #620.Near the Rancheria is the Yucaipa Adobe that is believed to be the oldest house in San Bernardino County. Diego Sepúlveda, nephew of Antonio María Lugo, built the Adobe in 1842 on land that was part of the Rancho San Bernardino granted in 1842 to the Lugos.
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