California State Route 91

State Route 91 (SR 91, locally referred to as the 91) is a major east–west state highway in the U.S. state of California that serves several regions of the Greater Los Angeles urban area. A freeway throughout its entire length, it officially runs from Vermont Avenue in Gardena, just west of the junction with the Harbor Freeway (Interstate 110, I-110), east to Riverside at the junction with the Pomona (SR 60 west of SR 91) and Moreno Valley (SR 60 and I-215 east of SR 91) freeways.

Though signs along Artesia Boulevard from Vermont Avenue west to Pacific Coast Highway (SR 1) in Hermosa Beach continue to mark it as part of SR 91, control of this segment of the highway was relinquished to local jurisdictions in 2003 and are thus no longer officially part of the state highway system.

SR 91 inherited its route number from the mostly decommissioned U.S. Route 91 (US 91), which passed through the Inland Empire in a northeasterly direction on its way to Las Vegas, Salt Lake City, and points beyond. Those segments of US 91 are now parallel to, or have been replaced altogether by, I-15.

From the Harbor Freeway (I-110) to its interchange with the Long Beach Freeway (I-710) in northern Long Beach, SR 91 is named the Gardena Freeway. Between the Long Beach Freeway and its interchange with the Santa Ana Freeway (I-5) in Buena Park, it is named the Artesia Freeway. From the Santa Ana Freeway to its eastern terminus at the interchange of the Pomona, Moreno Valley, and Escondido Freeways, it is named the Riverside Freeway.

Control cities on the route vary by location. When traveling westbound between SR 60/I-215 and the Orange County line, the listed control city is "Beach Cities". With SR 241 heading towards Irvine, Laguna Beach, and the rest of south Orange County, the control city becomes Los Angeles between the Orange–Riverside county line and I-5. I-5 directs travelers to Los Angeles, so between I-5 and Pioneer Boulevard, the control city is Artesia. Between Pioneer Boulevard and SR 1, the control city becomes Beach Cities again; besides Carmenita Road in Cerritos, the control city is in Long Beach. Heading eastbound, the control city for the entire route is Riverside. The Beach Cities control city may have to do with SR 91's former western terminus in Hermosa Beach.

SR 91 is part of the California Freeway and Expressway System and is part of the National Highway System, a network of highways that are considered essential to the country's economy, defense, and mobility by the Federal Highway Administration. SR 91 is part of the State Scenic Highway System from SR 55 to the east city limit of Anaheim, in the western part of the Santa Ana Canyon, and is eligible for the system through the canyon to Interstate 15.

The Gardena Freeway is a freeway in southern Los Angeles County. It is the westernmost freeway portion of State Route 91. It begins just west of the Harbor Freeway, at the intersection with Vermont Avenue in the eastern edge of the city of Gardena, proceeding eastward approximately six miles (9.7 km) until it intersects the Long Beach Freeway. Thereafter, SR 91 is known as the Artesia Freeway.

Until 1991, the Gardena Freeway was known as the Redondo Beach Freeway. The name change reflected the successful efforts of the cities of Torrance and Redondo Beach to block the extension of the freeway westward to its intended terminus at the cancelled Pacific Coast Freeway in Redondo Beach. In 1997, the California government dedicated the portion of SR 91 between Alameda Street and Central Avenue to former assemblyman Willard H. Murray Jr.