By jjron - Own work, GFDL 1.2, https://commons.wikimedia.org/w/index.php?curid=19458370
Union Station is located in the northeastern corner of Downtown Los Angeles, on the property bounded by Alameda Street, Cesar Chavez Avenue, Vignes Street, and the Hollywood Freeway. It is across Alameda Street from L.A.'s historic Olvera Street and El Pueblo de Los Angeles State Historic Park. The historic Terminal Annex building is on the opposite side of the Chavez Avenue underpass. Chinatown and Civic Center are a short distance away.
The Patsaouras Transit Plaza on the east side of Union Station hosts several connecting bus lines, including Metro Local, Metro Rapid and Metro Express lines, as well as downtown DASH shuttles, many municipal bus lines, FlyAway express bus service to Los Angeles International Airport, and University of Southern California campus shuttles. The Transit Plaza is named after Nick Patsaouras, former RTD board member and advocate for public transportation.
The Gateway Transit Center includes the station itself and the Patsaouras Transit Plaza, both of which were designed by Ehrenkrantz & Eckstut, along with the western terminus of the El Monte Busway, as well as Metro's headquarters building.
As of October 2019, Amtrak and Metrolink share 12 of Union Station's 14 outdoor tracks, with 94 trains departing on most weekdays (95 on Wednesday, 96 on Friday). 
PHOTOS COURTESY OF LA PUBLIC LIBRARY
It opened in May 1939 as the Los Angeles Union Passenger Terminal, replacing La Grande Station and Central Station. It was designed by the father-son architect team of John and Donald Parkinson with an innovative blend of Spanish Colonial, Mission Revival and Art Deco architecture now commonly referred to as Mission Moderne. The stunning facility was completed in 1939 for a reported $11 million (estimated in today’s dollars at $1.2 billion) and opened with a lavish, star-studded, three-day celebration attended by a half million Angelenos.
In the 8 decades since its opening, Union Station has captured the spirt and soul of Los Angeles and has emerged as a vital portal to the promise of the California dream. The station was designed as an expression of the California lifestyle with a spacious ticket hall equipped with a 110-foot-long ticket counter crafted from American Black Walnut, a vast waiting room featuring towering 40-foot windows adored with brass, massive art deco chandeliers, inlaid marble floors and hand painted mission tiles, along with expansive shaded patios, towering palm trees and a clock tower looming 100 feet above the city.
Within just a few years of opening, Los Angeles Union Station transformed into a bustling 24-hour, seven-day-a-week operation with as many as 100 troop trains carrying tens of thousands of servicemen through the terminal every day during World War II.
By the 1950’s Americans favored cars and planes to the rails and there were fewer passengers through the station but it remained a vital part of LA’s transportation scene for decades.
In 1972, Union Station was designated as a Los Angeles Historic–Cultural Monument and placed on the National Register of Historic Places in 1980. 
Some of this history is preserved in the University of Southern California Libraries Special Collections’ Union Station collection. It includes resources related to the planning and construction of the historic landmark, including correspondence, legal files, blueprints, maps, and planning documents — as well as digital images. 
PHOTOS COURTESY OF LA PUBLIC LIBRARY
Los Angeles Union Station Today
Complementing a cozy European bistro and lively brewpub and cocktail lounge, the station features several on-the-go eateries encompassing tastes from around the globe.
Please visit: https://www.unionstationla.com/dining-amenities for a full list of dining options and hours of operation.
Note: Some eateries are closed or limiting operating hours due to the pandemic. 
The station hosts a rotating collection of unique events, cutting edge performances, evocative music, unprecedented art exhibitions and thought-provoking cultural programing showcasing the diversity of entertainers, artists and innovators throughout Los Angeles. 
Please visit: https://www.unionstationla.com/previous-events for a full list of previous events.
California High-Speed Rail
Union Station is planned to be a major hub for the future California High-Speed Rail System. Upon completion, it is projected that passengers will be able to get from Union Station to the Transbay Transit Center in the city of San Francisco in 2 hours and 40 minutes.
As a part of its Master Plan, Metro is currently studying how to best integrate tracks and platforms for high-speed trains arrival into Union Station. Options include an aerial structure above the existing platforms, an underground structure under Alameda Street, an underground structure under Vignes and an aerial structure east of Vignes. All plans include a new concourse for high-speed rail passengers and three platforms with six tracks. 
 Librarian, Metro Digital Resources. “Union Station Is Born: The Story And Photos From The Citywide Fight Over A Central Rail Terminal.” Metro's Primary Resources, 2 May 2019, metroprimaryresources.info/72-years-ago-today-union-station-is-born-the-story-and-photos-from-the-citywide-fight-over-a-central-terminal-public-transit-plan/1169/.