On December 15, 1940, local subway service began on Sixth Avenue from the West Fourth Street subway station to the 47th–50th Streets station with track connections to the IND 53rd Street Line. The construction of the Sixth Avenue Line cost $59.5 million. The opening of the Sixth Avenue Line relieved train traffic on the Eighth Avenue Line, which was used by all services except for the G Brooklyn–Queens Crosstown service. The additional capacity allowed for the reintroduction of the AA for off-peak service between 168th Street and Hudson Terminal via the Eighth Avenue Line, and the creation of the rush-hour BB between 168th Street and 34th Street-Herald Square via Sixth Avenue. In addition, the D train, which ran between Norwood–205th Street and Hudson Terminal via Sixth Avenue, was introduced to provide service between Sixth Avenue and the Concourse Line. The F train, running between Parsons Boulevard and Church Avenue via Sixth Avenue, was created to provide express service between Sixth Avenue and Queens. Finally, the E train was cut back from Church Avenue to Broadway–Lafayette Street, running to Queens via the Eighth Avenue Line.