1990 July 14: Metro Blue Line opens between downtown Los Angeles and Long Beach (later renamed “A Line”)
1990 September 1: Metro Blue Line Long Beach Loop opens
1991 February 15: Metro Blue Line, Segment II opens between 12th/Pico Station and 7th/Flower Station in downtown Los Angeles.
1992 October 26: Once part of Metro, Metrolink begins operations
1993 January 30: Metro Red Line, Segment I opens between Union Station and 7th/Metro Station (later renamed “B Line”)
1995 July 12: Metro Green Line opens between Norwalk and Redondo Beach (later renamed “C Line”)
1996 July 15: Metro Red Line Segment IIA opens between Alvarado Street to Wilshire/Western Station (later renamed Purple Line, then again later renamed D Line)
2000 June 24: Metro Red Line Segment III opens between Hollywood/Vine and North Hollywood
2003 July 25: Metro Gold Line opens between downtown Los Angeles and Sierra Madre Villa Station in East Pasadena (later renamed “L Line”)
2005 October 29: Metro Orange Line opens, a 14-mile dedicated bus rapid transit line between North Hollywood and Woodland Hills (later renamed “G Line”)
2009 November 15: Metro Gold Line Eastside Extension opens between Los Angeles Union Station and East Los Angeles
2009 December 13: Metro Silver Line opens, a 38-mile bus rapid transit line between El Monte and Harbor Gateway / San Pedro, via downtown Los Angeles.
2012 April 27: Metro Expo Line, Phase I opens between downtown Los Angeles and Culver City (later renamed “E” Line)
2016 March 5: Metro Gold Line Foothill Extension opens from Sierra Madre Villa Station to Azusa Station
2016 May 20: Metro Expo Line, Phase II opens between Culver City and Santa Monica
2022 October 7: Metro Crenshaw Line (“K Line”) opens
2025 September 19: The Metro A Line extension to Pomona North opens