In 1955, the TA recommended that the Board of Estimate approve a contract to reconstruct a junction near the DeKalb Avenue station, on the Brooklyn side of the Manhattan Bridge, to eliminate a bottleneck there. This was the first step in a larger plan to improve transit service between Brooklyn and Manhattan. The Chrystie Street Connection would utilize the additional capacity created by reconstructing the tracks around DeKalb Avenue. fIn mid-1957, the New York City government solicited bids from contractors to construct the various parts of the connection. A groundbreaking ceremony was held on November 25, 1957, with Mayor Robert F. Wagner, Jr. and TA officials in attendance. The project was constructed in conjunction with the addition of express tracks on the Sixth Avenue Line between 34th Street and West 4th Street, adding capacity to the line. It was expected that the project would be finished in three years. In 1962, the Sixth Avenue extension to the new terminal at 57th Street was announced. During construction, the entire seven-block length of Chrystie Street was closed until 1964. The connection was projected to cost $100 million, and provide capacity for 52,000 more riders an hour between Brooklyn and Manhattan. Lighting, power and signal equipment for the Chrystie Street tunnel had been installed by January 1965. In 1965, the project was projected to be completed in 1967, with the portion involving the opening of the Grand Street station to be finished in 1966. To allow the Sixth Avenue Line express tracks to be connected, from July 11 to August 30, 1966, F trains terminated at Second Avenue instead of at the center tracks at Broadway–Lafayette Street. Opening The Manhattan Bridge connection and the Grand Street station opened on November 26, 1967, almost exactly 10 years after the project began. The Williamsburg Bridge connection and 57th Street station opened on July 1, 1968. The opening of the connection allowed greater flexibility in routings along BMT lines in Brooklyn. The Manhattan Bridge connection eliminated a bottleneck where trains using three of the four BMT Southern Division lines from Coney Island–Stillwell Avenue, were forced to use the Manhattan Bridge or the Montague Street Tunnel before going onto the BMT Broadway Line to Midtown Manhattan (or onto the Nassau Street Loop). The new connection thus permitted IND Sixth Avenue Line trains from Midtown to use the BMT lines toward Coney Island, while preserving Nassau Street service