SEPTA's Regional Rail division consists of 13 lines with 153 active stations, totaling of trackage. Each line is named by their station terminals, with the exception of the Manayunk/Norristown Line. The core of the Regional Rail system is the Center City Commuter Connection, a four-track tunnel under Center City linking three downtown stations: 30th Street Station, Suburban Station, and Jefferson Station. The Center City Commuter Connection was opened in 1984, built to connect the stub ends of the Pennsylvania Railroad and the Reading Railroad commuter rail systems. All SEPTA trains stop at the three downtown stations, with the exception of the Cynwyd Line (which terminates at Suburban Station). Most trains stop at Temple University station, located on the eastern edge of the Temple University campus. Because the tunnel makes the through-routing of trains possible, most inbound trains from one line continue as outbound trains on another line.