A The answer is quite simple: At each location, the railroads have joined together to operate a single facility. Many large cities had such stations, such as Los Angeles, Denver, Kansas City, St. Louis, Chicago, Nashville, and Jacksonville.
Chicago Union Station, for example, was a joint venture of the Chicago, Burlington & Quincy; Milwaukee Road; and Pennsylvania Railroad through the jointly owned Chicago Union Station Co. (The Gulf, Mobile & Ohio, which also called at the facility, was a non-owner tenant.)
Smaller cities could also benefit from joint-use facilities, such as Effingham, Ill.; Marion, Ohio; and Bethlehem, Pa. Passengers were able to connect between multiple railroads’ passenger trains, without changing stations. – Brian Schmidt
Of course, I am loyal to my hometown Union, St. Louis and it was owned by Terminal Railroad which did all the switching for the passenger trains. It was stub end and I remember passing the station and then backing into the huge shed area. It was built in 1894 and was one of the busiest stations in US in the early years. My parents and I always left from there and also when I took trips with friends pre-Amtrak. They used it for a few years but moved out in 1978. It sat empty until about 1985 when it was developed into a shopping mall and hotel. Its’ new owners are very train friendly and we do run annual Polar Express from there. Huge remodeling has taken place in the last few years. But Amtrak uses Gateway center built in 2008 where they share space with Greyhound and Mega bus. I wish they still used Union Station but I am glad it was preserved and not torn down like many others.
Pittsburgh Pennsylvania Station was not a union station but the Bessemer and Lake Erie was a tenant for its local passenger service until about 1953.
Glad to know the Brotherhood of Railway Trainmen was not involved.
I have heard that Union Station in Washington, DC got its name not only because it brought together the stations of several railroads, but also to emphasize solidarity with the Union after the civil war, ~40 years earlier.
The Union Station at Hedrick, Iowa, still standing, was used by the Milwaukee Road and the M&StL. It is likely the smallest Union Station in size, and still looked great last time I saw it. Milwaukee Road ran north to Cedar Rapids and south to Kansas City via Ottumwa just a few miles south. The M&StL ran west to Oskaloosa and east to Peoria. One Sunday afternoon, circa 1948, my dad drove eastward on a parallel road and we were passed by an M&StL doodlebug which was amazing to a ten year old. I think Hedrick Union Station had once served an Iowa Central line that ran east to the Mississippi River towns. The M&StL and IowaC lines were parallel running eastward.
The Burlington station in Ottumwa, Iowa was also a union station as it also served the Rock Island.
My favorite is Union Station in Pittsburgh. The Pennsylvania Railroad built it and it was only used by them and the roads owned or controlled by them. I haven’t found any other major railroad that used the station. “Union” only by broadest use of the word.
The Hot Springs, SD Union Station (CB&Q/C&NW) has been mentioned as the smallest. Both station and railroads are gone.
The Los Angeles Union Passenger Terminal (LAUPT), which opened in 1939, was the result of an effort involving the three major railroads in LA at the time–Union Pacific, Southern Pacific, and Santa Fe. The LAUPT has seen both good days (e.g., during World War II, when the place was incredibly busy) and bad days (when passenger service became an albatross for the railroads). However, the terminal is still in use today. It supports passenger service for Amtrak, as well as for the interurban rail system in LA.
I know of a former station in Grinnell Iowa that served both the Minneapolis and St Louis and the Chicago Rock Island and Pacific that transferred passengers between the two lines. It is now a restaurant, but could be a small example of a union station.
There is a Union Station in Selma N.C. It was a joint partnership between Amtrak, Norfolk Southern, and CSX.
The Port Kent, NY seasonal Amtrak station is jokingly known as Port Kent “Union” station, due to the fact the the Keysville, Ausable Chasm, and Lake Champlain RR(KAC&LC), also known as the “peanut railroad”.
The depot in Little Rock, Ark has “Union Station” signage. The former Rock Island Line “Choctaw Route” depot is east of “downtown” . What other passenger service called on Little Rock, Ark., other than Missouri Pacific to elevate the facility to “Union Station” status ?
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