Express trains began running on April 24, 1939, to serve the 1939 New York World's Fair. The first train left Main Street at 6:30 a.m. IRT expresses ran every nine minutes between Main Street and Times Square, while BMT expresses ran every minutes between Main Street and Queensboro Plaza. The running time between Main Street and Queensboro Plaza was 15 minutes and the running time between Main Street and Times Square was 27 minutes. Express service to Manhattan operated in the morning rush between 6:30 and 10:43 a.m. Express service to Main Street began from Times Square for the IRT at 10:50 a.m. and the BMT from Queensboro Plaza at 11:09 a.m., continuing until 8 p.m.