On November 26, 1967, the first part of the Chrystie Street Connection opened and Sixth Avenue Line express tracks opened from 34th Street–Herald Square to West Fourth Street–Washington Square. With the opening of the connection to the Manhattan Bridge, BB service was renamed B and it was extended via the new express tracks and the connection to the BMT West End Line in Brooklyn. D service was routed via the connection and onto the BMT Brighton Line instead of via the Culver Line. It only ran express during rush hours. F service was extended from Broadway–Lafayette Street during rush hours, and from 34th Street during other times to Coney Island via the Culver Line. On July 1, 1968, the 57th Street station and the portion of the Chrystie Street Connection connecting the line with the Williamsburg Bridge opened. Service on the KK was inaugurated, running from 57th Street to 168th Street on the BMT Jamaica Line. B service was extended during non-rush hours from West Fourth Street to 57th Street. D trains began running express via the Sixth Avenue Line at all times.