train (now retired) leaving
Downtown Long Beach station.
Long Beach Line Much of the initial segment of the A Line from Downtown Los Angeles to Long Beach follows the route of the
Pacific Electric's
Long Beach Line, which ended service in 1961. The old route gave the new light rail trains a private right of way between and stations allowing them to reach higher speeds between stops. The line initially opened as the Blue Line on Saturday, July 14, 1990, and ran from to . The Long Beach Loop section to opened in September 1990, followed by the tunnel into in February 1991. The initial light rail segment cost US$877 million ($ in adjusted for inflation). The route reached full capacity after one decade of service, and from 1999 to 2001, the Blue Line underwent a US$11 million project to lengthen 19 of its platforms to accommodate three-car trains. There were also plans since the 1980s to extend the Blue Line north to Pasadena but the connection through downtown was postponed due to funding constraints from the voter-approved 1998 Proposition A. The proposition restricted local county subway funding, halting the process of the Blue Line extension and other
rail transit projects from advancing. The Blue Line was renovated in 2019, with the southern half of the line being closed for the first five months and the northern half closing for the following five months (10 months total). Metro provided a bus shuttle service to compensate for the lack of rail service. Metro officially reopened the line on November 2, 2019, rebranding it as the A Line. The renovation helped improve the line's speed and reliability by replacing and modernizing old tracks, signals, train control systems, and bridges.
Pasadena Blue Line train at
Chinatown station Much of the A Line's right of way north of through the
San Gabriel Valley was built by the
Los Angeles and San Gabriel Valley Railroad in 1885. It was eventually taken over by the
Atchison, Topeka and Santa Fe Railway, as part of the
Pasadena Subdivision, which saw
Amtrak service until 1994, when construction began on the conversion to light rail. The light rail project was initially called the "Pasadena Metro Blue Line." Planners envisioned extending the existing Blue Line (A Line) north of 7th Street/Metro Center, but it was canceled due to funding shortages. However, the mostly above-ground segment of the extension from Union Station to Pasadena advanced and began construction in 1994 as a separate line but was suspended again by 1998 due to the Proposition A ban. Later that year, a bill was authorized to create a new independent construction authority to finish the line. The agency, now known as the Foothill Gold Line Construction Authority, resumed light rail construction in 2000 and completed the line three years later.
Foothill Extension Phase 2A was not yet installed. In 2016, the Gold Line was extended east from Pasadena as part of Phase 2A (Phase 1 was the initial Los Angeles to Pasadena segment) of the
Foothill Extension, running between Sierra Madre Villa and stations in Azusa. The extension was constructed by the Foothill Gold Line Construction Authority and added six new stations to the Gold Line serving the cities of Arcadia, Monrovia, Duarte, Irwindale, and Azusa. A groundbreaking ceremony for Phase 2A was held on June 26, 2010; construction began the following summer and was completed in September 2015, with the extension entering service on March 5, 2016. Like other lines in the Los Angeles Metro system, the Gold Line's designation became a letter in 2020. This was the beginning of a process where all Metro Rail and Busway lines would be identified by a letter name rather than a system of colors. The Gold Line was renamed to the L Line.
Regional Connector The Regional Connector Transit Project constructed a light rail tunnel across Downtown Los Angeles that connected A and E lines to the L Line, with the purpose of reducing transfers and travel times through downtown. The project completed the late 1990s vision of the "Pasadena Blue Line," connecting the northern (Union Station–Azusa) segment of the L Line to the A Line. This enabled A Line trains to run from Long Beach to Azusa through the new tunnel. The southern (
Pico/Aliso–
East LA) segment was combined with the existing E Line between Downtown Los Angeles and
Santa Monica. The new east-west line kept the E Line name but uses the L Line's gold color. Two new stations were also constructed in the tunnel, providing more service to destinations and communities in Downtown Los Angeles. Formal studies and planning for the Regional Connector began in 2004 and was approved in 2012. A groundbreaking ceremony was held on September 30, 2014, marking the start of major construction. To accommodate the new tunnel, the existing at-grade L Line
Little Tokyo/Arts District station was demolished in 2020 and rebuilt as a subway station approximately south and on the opposite side of Alameda Street from its former location. Starting on April 9, 2023, the A, E, and L Line trains ran through the Regional Connector tunnel for final testing. The project officially opened for revenue service on June 16, 2023. Once the Regional Connector was completed, the alignment of the L Line was split into two parts at Little Tokyo/Arts District station, with the portion north of the station joined to the A Line, extending it to connect Long Beach with Azusa. With this change, the A Line officially became the longest, modern day light rail line in the world. The alignment east of Little Tokyo/Arts District station was assigned to the E Line, extending it to connect Santa Monica and
East Los Angeles directly. At this time, the L Line ceased to exist as a separate line.
Foothill Extension Phase 2B to Pomona The first part of Phase 2B of the Foothill Extension, running between APU/Citrus College station in Azusa and
Pomona North station in Pomona, opened on September 19, 2025. This section, like the original Gold Line to Pasadena, and Phase 2A of the Foothill Extension, was built by the Foothill Gold Line Construction Authority (Foothill Gold Line). == Future developments ==