Question: Newhall is a rail station in the city of Santa Clarita, California, the station is served by Metrolink's Antelope Valley Line operating between Los Angeles Union Station, the main railway station in Los Angeles, California, and the largest railroad passenger terminal in the Western US, and Lancaster and Amtrak Thruway Motorcoach buses to Bakersfield, opened when?
Context: State Route 14 (SR 14) is a north–south state highway in the U.S. state of California, largely in the Mojave Desert.  The southern portion of the highway is signed as the Antelope Valley Freeway.  The route connects Interstate 5, or Golden State Freeway, on the border of the city of Santa Clarita to the north and the Los Angeles neighborhoods of Granada Hills and Sylmar to the south, with U.S. Route 395 near Inyokern.  Legislatively, the route extends south of I-5 to State Route 1 in the Pacific Palisades area of Los Angeles, however the portion south of the junction with I-5 has not been constructed.  The southern part of the constructed route is a busy commuter freeway serving and connecting the cities of Santa Clarita, Palmdale, and Lancaster with the rest of the Greater Los Angeles area.  The northern portion, from Vincent (south of Palmdale) to Route 395, is legislatively named the Aerospace Highway, as the highway serves Edwards Air Force Base, once one of the primary landing strips for NASA's Space Shuttle.  This section is rural, following the line between the hot Mojave desert and the forming Sierra Nevada mountain range.  Most of Route 14 is loosely paralleled by a main line of the Southern Pacific Railroad, used for the Antelope Valley Line of the Metrolink commuter rail system as well as a connection between Los Angeles and the Central Valley via Tehachapi Pass. Santa Clarita is a Metrolink rail station in the city of Santa Clarita, California.  It is served by Metrolink's Antelope Valley Line from Los Angeles Union Station to Lancaster.  30 Metrolink trains serve the station each weekday and 12 serve the station on Saturday and Sunday.  Sunday service began in September 2007.  Weekday Metrolink service runs primarily at peak hours in the peak direction of travel while weekend departures and arrivals are fairly evenly spaced throughout the day.  City of Santa Clarita Transit offers connecting bus service at the station.  Because the city of Santa Clarita has two other Metrolink stations, this station is sometimes referred to as Soledad Metrolink. The Vincent Grade/Acton Metrolink Station is a Metrolink rail station just north of the community of Acton, California.  It is served by Metrolink's Antelope Valley Line from Los Angeles Union Station to Lancaster. Downtown Burbank is a passenger rail station near downtown Burbank, California.  It is served by Metrolink's Antelope Valley Line to Lancaster and Ventura County Line to East Ventura with both terminating at Los Angeles Union Station.  Amtrak trains do not stop at this station; rather, Amtrak trains stop at the Burbank Airport station, adjacent to Bob Hope Airport, several miles to the northwest of downtown Burbank.  Megabus started providing long distance motorcoach service from the station on August 15, 2013. Via Princessa is a Metrolink rail station located in the city of Santa Clarita, California.  It is served by Metrolink's Antelope Valley Line from Los Angeles Union Station to Lancaster. Newhall is a rail station in the city of Santa Clarita, California.  The station is served by Metrolink's Antelope Valley Line operating between Los Angeles Union Station and Lancaster and Amtrak Thruway Motorcoach buses to Bakersfield. Lancaster is a Metrolink train station in the city of Lancaster, California, United States.  It is served by Metrolink's Antelope Valley Line from Los Angeles Union Station to Lancaster.  18 Metrolink trains serve the station each weekday and 12 serve on weekends.  Weekday Metrolink service runs primarily at peak hours in the peak direction of travel while weekend departures and arrivals are fairly evenly spaced throughout the day. Sylmar/San Fernando is a Metrolink rail station located in Sylmar, California, (a neighborhood of Los Angeles in the San Fernando Valley) and adjacent to the city of San Fernando.  Metrolink's Antelope Valley Line from Los Angeles Union Station to Lancaster has 30 trains each weekday and 12 trains stopping on Saturday and Sunday. Los Angeles Union Station (LAUS) is the main railway station in Los Angeles, California, and the largest railroad passenger terminal in the Western United States.  It opened in May 1939 as the Los Angeles Union Passenger Terminal, replacing La Grande Station and Central Station. The Sun Valley Metrolink Station is a Metrolink rail station in the community of Sun Valley, Los Angeles, California.  It is served by Metrolink's Antelope Valley Line from Los Angeles Union Station to Lancaster.  28 Metrolink trains serve the station each weekday and 12 serve the station on Saturday and Sunday.  Weekday Metrolink service runs primarily at peak hours in the peak direction of travel while weekend departures and arrivals are fairly evenly spaced throughout the day.
Answer: May 1939