The 15 line runs along Girard Avenue through Greater Kensington, North Philadelphia, and West Philadelphia. The trolley utilizes restored PCC streetcars, a type of heritage trolley built in the 1930s. The trolleys were rebuilt with added air conditioning and regenerative braking. Route 15 is the only active trolley line in Philadelphia that is not part of the Subway-Surface Trolley Line system. 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. The PATCO Speedline is a grade-separated system linking Philadelphia to the cities of Camden, Haddonfield, and Lindenwold in New Jersey. The Speedline has a daily ridership of 38,000, and is the primary transit link between South Jersey and Philadelphia. It is operated by the Port Authority Transit Corporation, a subsidiary of the Delaware River Port Authority (DRPA), and is the only rail line in Philadelphia to operate 24 hours a day during the week. According to a study conducted by the Delaware Valley Regional Planning Commission, 95% of riders are New Jersey residents, and the Speedline carries 47% of New Jersey business commuters with jobs in Center City. NJ Transit operates the Atlantic City Line from 30th Street Station to Atlantic City, New Jersey. Historically run by the Pennsylvania-Reading Seashore Lines, the current line opened in 1989 by Amtrak as the ""Gambler's Express"" and has been operated solely by NJ Transit since 1996. The line has six intermediate stops in New Jersey, with 13-16 departures in each direction per day. Intercity train service is operated out of 30th Street Station by Amtrak. Amtrak runs most services along the electrified Northeast Corridor, serving a densely urbanized string of cities in the northeastern United States.