22nd Street is an underground tram station for the SEPTA Subway–Surface Trolley Lines, in Center City, Philadelphia. Similar to 19th Street Station, the station has two side platforms with a total of four tracks. Only the two outer tracks serve the station; the two inner tracks are used for the Market-Frankford Line as it travels between 15th Street and 30th Street. Since the station is only served by the trolley lines, there is no fare collection at the station; all fares are paid on board the trolley itself.