Barstow is a city in San Bernardino County, California, United States. The population was 22,639 at the 2010 census, up from 21,119 at the 2000 census. Barstow is located 55 miles (89 km) north of San Bernardino. Barstow is a major transportation center for the Riverside-San Bernardino metropolitan area. Several major highways including Interstate 15 and Interstate 40 converge in the city. It is the site of a large rail classification yard, belonging to the BNSF Railway.