The Ventura Freeway is a freeway in southern California, United States, running from the Santa Barbara/Ventura county line to Pasadena in Los Angeles County. It is the principal east-west route (designated north-south) through Ventura County and in the southern San Fernando Valley in Los Angeles County. From the Santa Barbara County line to its intersection with the Hollywood Freeway in the southeastern San Fernando Valley in Los Angeles (the Hollywood Split), it is signed as U.S. Route 101 (US 101), which was built in the late 1950s and opened on April 5, 1960. East of the Hollywood Freeway intersection, it is signed as State Route 134 (SR 134) which was built by 1971.