Interstate 405 (also referred to as "I-405" and "The 405") is one of the principal north-south interstate highways in Southern California, and the major bypass of Interstate 5 running through the Greater Los Angeles Area. The entire 405 is known as the northern segment of the San Diego Freeway, despite being 75 miles (121 km) away from downtown San Diego. I-405 is a heavily-traveled thoroughfare by commuters and freight haulers along its entire length and has earned its place as one of the busiest and most congested freeways in the world, and the most congested in the United States. [2] [3] It has played a crucial role in the development of dozens of cities and suburbs along its route through the Greater Los Angeles area.
