The Interstate 605 number is also used for a planned bypass of Seattle, Washington.

The San Gabriel River Freeway is the name assigned to Interstate 605, a major north-south freeway of about 27 miles in length located entirely within Southern California. Unlike most other freeways in California which are named after a particular city along its route, this freeway derives its name from the San Gabriel River that it parallels for most of its alignment.

The route

The north terminus of the freeway is at the junction with the Foothill Freeway, Interstate 210 (I-210) in Duarte, California, a small city located at the foothills of the San Gabriel Mountains. The alignment of the freeway is generally south-southwest and passes through the western San Gabriel Valley, shifting straight south as it crosses the Whittier Narrows into the Los Angeles Basin. After traveling through the Gateway Cities region of southeastern Los Angeles County, it crosses Coyote Creek into Orange County, where it terminates at the junction of the San Diego, Interstate 405 (I-405) and Garden Grove, California State Highway 22 (CA/SR-22) Freeways in Seal Beach, California.

Cities/Communities along the San Gabriel Freeway (north to south)

• Duarte
• Irwindale
• Baldwin Park
• Industry
• Pico Rivera
• Whittier
• Santa Fe Springs
• Downey
• Norwalk
• Cerritos
• Lakewood
• Hawaiian Gardens
• Long Beach
• Los Alamitos
• Rossmoor
• Seal Beach

Major Freeways/Highways intersecting with the San Gabriel Freeway (north to south)

• Foothill Freeway - Interstate 210 (I-210) in Duarte
• San Bernardino Freeway - Interstate 10 (I-10) in Baldwin Park
• Pomona Freeway - California State Highway 60 (CA/SR-60) in City of Industry
• Whittier Boulevard (surface street) - California State Highway 72 (CA/SR-72) in Whittier
• Santa Ana Freeway - Interstate 5 (I-5) in Santa Fe Springs
• Century/Glenn M. Anderson Freeway - Interstate 105 (I-105) in Norwalk
• Artesia Freeway - California State Highway 91 (CA/SR-91) in Cerritos
• San Diego Freeway - Interstate 405 (I-405) in Seal Beach
• Garden Grove Freeway - California State Highway 22 (CA/SR-22) in Seal Beach