I405

The I-405, officially the Interstate 405, is a major Interstate Highway in the U.S. state of California. It is a significant spur route of Interstate 5, hence the designation "405". The freeway is known for its heavy traffic volume and its importance as a major artery through the Los Angeles metropolitan area. Its full name is the Christopher W. Holden Memorial Freeway.

The I-405 runs for approximately 71 miles, beginning at its southern terminus at Interstate 5 in San Diego and continuing north to its northern terminus at U.S. Route 101 in Los Angeles. It passes through numerous cities and communities, including Irvine, Costa Mesa, Long Beach, Torrance, and Inglewood. Key interchanges include connections with other major freeways such as the I-5, I-10, SR 22, and US 101.

The freeway is a critical component of the Southern California transportation network, serving millions of residents and facilitating commerce. Its proximity to Los Angeles International Airport (LAX) makes it a vital route for travelers. Due to its high traffic density, the I-405 is frequently subject to congestion, especially during peak commute hours. Various projects have been undertaken over the years to expand its capacity, including the addition of carpool lanes and other improvements.