The Columbian was a named passenger train operated by the Baltimore and Ohio Railroad. It was the all-coach supplemental train of the all-Pullman Capitol Limited. It operated from 1931 to 1964. The train's initial route was between Jersey City, New Jersey and Washington, D.C., but in 1941 the Columbian route was lengthened to Jersey City – Chicago, Illinois. It was the first air-conditioned train in the United States.

The Capitol Limited was an American passenger train run by the Baltimore and Ohio Railroad, originally between New York City and Grand Central Station in Chicago, Illinois, via Union Station, Washington, D.C., Baltimore and Pittsburgh. For almost 48 years, it was the B&O's flagship passenger train, noted for personalized service and innovation. At the time of its discontinuation on May 1, 1971, when Amtrak took over most rail passenger service in the U.S., the Capitol Limited operated between Washington and Chicago.