Pennsylvania Union Station
In 1898, Alexander Cassatt, president of the Pennsylvania Railroad and brother of painter Mary Cassatt, comissioned Chicago architect Daniel H. Burnham to design a station/hotel/office building to serve Pittsburgh.
Burnham, a skyscraper pioneer who created the Flatiron Building in New York and Union Station in Washington, and supervised the "White City" of Chicago's World's Columbian Exposition in 1893, designed this classic structure for Cassatt and the PRR.
The best feature of Union Station, which was completed in 1903, is the elaborately styled rotunda that sheltered passengers dismounting from their carriages.
This is one of the design elements inside the rotunda that features Pittsburg with its missing "h," which was removed by the U.S. Board on Geographic Names in 1891. It was restored in 1911.
The building was converted to apartments and ground-floor office space in the mid-1980s and serves as Pittsburgh's Amtrak station.
The routunda entered the National Register of Historic Places in 1973 while the entire building joined in 1976.
For more on Burnham's facinating career, see: en.wikipedia.org/wiki/Daniel_Burnham