The NRG Station contains a lower level platform (but very narrow compared to the very wide upper level platform), built to accommodate additional trains for large crowds at sporting events. Seldom used in recent years, these tracks are most often used to store rolling stock and work trains. Two of the Broad Street subway system's stations have been closed: Spring Garden station (closed in 1991) on the Ridge Avenue spur line and Franklin Square station on the PATCO route (closed in 1953 and later opened in 1976 for Bi-Centennial and then closed again in 1979).