California State Route 91 is a major east-west freeway located entirely within Southern California. This freeway serves multiple communities in the Los Angeles metropolitan area. Its eastern terminus is located in Riverside at the junction with the Pomona/Moreno Valley Freeway, California State Highway 60 (CA/SR-60). Its western terminus is located just west of the junction with the Harbor Freeway, Interstate 110 (I-110) near Gardena. West of this junction, the freeway becomes a regular suface street (but continues with the CA/SR-91 assignment).

From the Harbor Freeway to its intersection with the Long Beach Freeway in northern Long Beach, it is named the Gardena Freeway. Between the Long Beach Freeway and its intersection with the Santa Ana Freeway in Fullerton, it is named the Artesia Freeway. From the Santa Ana Freeway to its eastern terminus at the intersection of the Pomona/Moreno Valley Freeway (CA/SR-60), CA/SR-91 is named the Riverside Freeway.

Although CA/SR-91 is an east-west road, it inherited its odd (as opposed to even) number from the now mostly decommissioned U.S. Route 91 (U.S. 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 U.S. 91 now parallel, or have been replaced altogether, by Interstate 15 (I-15).

CA/SR-91 traverses (from west to east) through Los Angeles, Orange, and Riverside counties.

91 Express Lanes

By the early 1990s, rapid development of the areas of the Inland Empire around Riverside had made the Riverside Freeway-which is the sole freeway connecting the working-class bedroom communities and industrial areas of the Inland Empire to the wealthy suburbs and commercial centers of Orange County--one of the most congested in the Greater Los Angeles region. In response, a private consortium created the 91 Express Lanes, a fully automated, radio-transponder-activated tollway contained entirely within the median of the existing Riverside Freeway. This route operates between the Orange/Riverside county line and the Costa Mesa Freeway interchange in eastern Anaheim. Opening in 1995, the 91 Express Lanes were the first privately funded tollway built in the United States since the 1940s, and the first fully automated tollway in the world. In 2003, their ownership and operation was taken over by the Orange County Transportation Authority[1].

Cities/Communities along CA/SR-91 (west to east)

• Torrance
• Lawndale
• Gardena
• Harbor Gateway
• Carson
• Compton
• Long Beach
• Bellflower
• Cerritos
• Artesia
• La Palma
• Buena Park
• Fullerton
• Anaheim
• Placentia
• Yorba Linda
• Coronita
• Corona
• Riverside

Major Freeways/Highways intersecting with CA/SR-91 (west to east)

• Harbor Freeway - Interstate 110
• Long Beach Freeway - Interstate 710
• San Gabriel River Freeway - Interstate 605
• Santa Ana Freeway - Interstate 5
• Orange Freeway - California State Highway 57
• Newport/Costa Mesa Freeway - California State Highway 55
• Foothill/Eastern Corridor (Toll Road) - California State Highway 241
• Corona/Chino Hills Freeway - California State Highway 71
• Ontario Freeway - Interstate 15
• Pomona Freeway/Moreno Valley Freeway - California State Highway 60