The Philadelphia Train System is operated by SEPTA, which stands for Southeastern Pennsylvania Transportation Authority. SEPTA is a regional public transportation authority that operates bus, subway, trolley, and commuter rail services in the Philadelphia metropolitan area. SEPTA is the sixth-largest public transit system in the United States, with over 300 million annual riders. SEPTA provides service to more than 3 million people in five counties in Pennsylvania, as well as parts of New Jersey and Delaware.