C Line (Los Angeles Metro)

The C Line (formerly the Green Line from 1995 to 2020) is a 17.8-mile (28.6 km) light rail line running between the Los Angeles neighborhood of Westchester and the city of Norwalk in southwestern Los Angeles County, California. It is one of six lines forming the Los Angeles Metro Rail system and opened on August 12, 1995. Along the route, the line also serves the cities of Downey, Hawthorne, and Lynwood, as well as several unincorporated communities in the South Los Angeles region including Athens, Del Aire, and Willowbrook. The fully grade-separated route runs mainly in the median strip of Interstate 105 for its latitude portion and in a mixture of viaducts, embankments, and an open trench for its western leg. While still being part of the bigger Metro Rail light rail network, this grade-separated alignment technically puts the line in the light metro category. A free shuttle bus to Los Angeles International Airport (LAX) is available at the LAX/Metro Transit Center.

On November 3, 2024, the C and K lines underwent service changes to accommodate pre-revenue testing at the then-upcoming LAX/Metro Transit Center, which opened on June 6, 2025. The C Line's western terminus was redirected to Aviation/Century station and the southern segment of the K Line was created between Aviation/Century station and Redondo Beach station. Upon the opening of the LAX/Metro Transit Center, the C Line now terminates at this station, and the K Line now operates as a single, continuous service through it. The LAX Automated People Mover, which will offer a connection to the airport's terminals, will begin service at the LAX/Metro Transit Center in 2026.