Union Station, also known as Pennsylvania Station and commonly called Penn Station, is a historic train station in Downtown Pittsburgh, Pennsylvania. It was one of several passenger rail stations that served Pittsburgh during the 20th century; others included the Pittsburgh & Lake Erie Railroad Station, the Baltimore and Ohio Station, and Wabash Pittsburgh Terminal, and it is the only surviving station in active use. The historic station was designed by Chicago architect Daniel Burnham and built from 1898 to 1904. The station's rotunda was added to the National Register of Historic Places in 1973, followed by the entire building in 1976. In the 1980s, the Burnham station building was converted to apartment use, while Amtrak moved to an annex on the building's east side. History The current station replaced the original Union Station which was destroyed in the Pittsburgh railroad strike of 1877. Unlike many union stations built in the U.S. to serve the needs of more than one railroad, this facility only served the Pennsylvania Railroad and its subsidiary lines; for that reason, it was renamed in 1912 to match other Pennsylvania Stations. Thus, Union Station is a misnomer, as other major passenger rail carriers served travelers at other stations. For instance, the New York Central used Pittsburgh & Lake Erie Railroad Station, the Wabash Railroad used Wabash Pittsburgh Terminal, and the Baltimore and Ohio Railroad used both the Baltimore and Ohio Station and the Pittsburgh & Lake Erie Railroad Station. The station building was designed by Chicago architect Daniel Burnham and built between 1898–1904. The materials were a grayish-brown terra cotta that looked like brownstone, and brick. Though Burnham is regarded more as a planner and organizer rather than a designer of details, which were left to draftsmen like Peter Joseph Weber, the most extraordinary feature of the monumental train station is his: the rotunda with corner pavilions. At street level, the rotunda sheltered turning spaces for carriages beneath wide, low vaulted spaces that owed little to any historicist style. Above, the rotunda sheltered passengers in a spectacular waiting room. Burnham's firm completed more than a dozen projects in Pittsburgh, some on quite prominent sites. The rotunda is listed on the National Register of Historic Places. Service began at the station on October 12, 1901. On January 3, 1954, the Pennsylvania Railroad announced a in expansion and renovation for the complex. To the beginning of the 1970s, the