Pennsylvania Station (often abbreviated Penn Station) is a name applied by the Pennsylvania Railroad (PRR) to several of its grand passenger terminals. Several are still in active use by Amtrak and other transportation services; others have been demolished. In the early 20th century, different railroad companies typically built separate stations, especially in major cities or towns, so the stations usually took the name of the companies. If various railroads cooperated to use the same station, the combined depot often took the name Union Station.