Penn Station is a unique combination of a classic Beaux-Arts architectural design from architect Kenneth Mackenzie Murchison and a functional, adaptable train station that serves as the eighth busiest station in the United States. Originally known as the Union Station, named for the Union of northern and southern railroads that came together at the station, this 1911 ornate granite, terra cotta, and cast iron building is the third structure to exist on the site.
In 1873, the Northern Central Railway building built the first station, a wooden structure, replaced in 1886 with a hulking Victorian brick structure. After critics declared the station to be overcrowded, uncomfortable, dangerous, and unsuitable for Baltimore's booming passenger traffic, the station was torn down in 1910 to be replaced by a new modern station. The architect, Kenneth Mackenzie Murchison, had extensive experience creating railroad stations around the nation and brought a stylish Beaux-Arts style to the job. Murchison's design incorporated an innovative waiting area illuminated by three large domed skylights directly connected to the boarding platforms.
The Pennsylvania Railway Company took over the station in the 1920s and renamed it Pennsylvania Station to match the other Penn Stations along the line. The building deteriorated over the years and during World War II blackout paint was applied to the skylight and windows. This remained through the early 1980s, when a $5 million facelift restored the mosaic flooring, glazed wall tile, marble detailing, and the windows. In 2015, the station served more than 993,721 Amtrak passengers and even more of MARC train commuters.