IRT used both sides of the current platforms, and the BMT used now-demolished platforms north of the current platforms, also double-decked. The south side of the IRT platforms was used by the Flushing Line, as today. The north side was used by Astoria trains, but instead of going through the 60th Street Tunnel, they went over the Queensboro Bridge to the elevated IRT Second Avenue Line. Double crossovers south (lower tracks) and north (upper tracks) of the platforms allowed trains from either side to switch to the other line after leaving the station. At the BMT half, the south track served subway trains to Manhattan and the BMT Broadway Line. By 1924, trains came from Manhattan on the upper level, continued north to a merge with the lower level, and then returned via the lower level. Before that, trains reversed direction using a double crossover south of the platforms. Since the platforms were IRT-size, the BMT used its own elevated cars to provide service on the lines, with a required transfer at Queensboro Plaza. Shuttles from Astoria came in on the west side lower track and then reversed direction to head to Flushing; Flushing trains came in on the upper track and reversed direction towards Astoria. During the early period of dual service on the Astoria and Flushing portions, IRT and BMT trains had their own stopping marks on the platforms and the sections of the platforms were separated. Passengers had separate entrances to the platforms depending on which service they wanted. This set-up prevented free transfers between the trains of the two companies. This arrangement had to end when the IRT lengthened trains. The two companies worked out an agreement in which the revenue collected on those stations was shared. After 1949, the track layout around the station was greatly simplified. Only the original southern side of the Queensboro Plaza station remains in service, with two tracks on each level. Queens-bound trains use the upper level, while Manhattan-bound trains use the lower level. BMT trains use the northern tracks on each level and IRT trains use the southern tracks. A double crossover remains on the upper level. Exits The station's only exits are through a mezzanine located below the lower level (and formerly connected to the now torn-down BMT platforms to the west). From the mezzanine, there is a concrete ramp across Queens Plaza North to the second floor