Phoenix is the largest metropolitan city in the U.S. without passenger-rail service, but that wasn't always the case. 
In 1923, Phoenix Union Station opened. And in 1926, a transcontinental line was completed, meaning someone could take the train anywhere in the country. 
In this episode of Valley 101, a podcast from The Arizona Republic and azcentral.com, we're exploring the history of passenger-rail service in the Valley. We'll look at what caused the decline in ridership, as well as future plans that could revive rail service to the historic building.