This construction tied into the existing lower level of the BMT Brighton Line east of West Eighth Street–New York Aquarium. Some Culver Line (5) trains began using the Fourth Avenue Subway to the Nassau Street Loop in Lower Manhattan when that line opened on May 30, 1931; the Fifth Avenue Elevated was closed on May 31, 1940, in conjunction with the unification of the transit system under city operations. Trolleys continued to use the surface tracks on McDonald Avenue until October 30, 1956.
