via the Montague Street Tunnel. Trains from the BMT Jamaica Line and other BMT Eastern Division lines also gained a direct connection to Midtown Manhattan via the Sixth Avenue Line by using the Williamsburg Bridge connection. The Chrystie Street Connection was the first actual integration of BMT and IND lines after the unification of all major lines under New York City municipal ownership in 1940. Prior to that, the nearest integration of the two previous systems was the operation of BMT trains over part of the IND Queens Boulevard Line via the BMT 60th Street Tunnel Connection connecting Lexington Avenue/59th Street on the BMT Broadway Line to Queens Plaza on the IND Queens Boulevard Line in 1955. In that case, however, BMT trains operated on the IND by trackage rights, using BMT equipment and crews. Service changes Two major service changes were inaugurated with the opening of the connection. The first went into effect on Sunday, November 26, 1967, when the Manhattan Bridge connection opened. The second occurred on Monday, July 1, 1968, when the Williamsburg Bridge connection opened. Additionally, for the 1967 opening, every service in the system was labeled with a letter or number and a color. Original changes Changes following the Manhattan Bridge connection opening On November 15, 1967, the TA published a subway map showing which routes would be changed when the Manhattan Bridge connection opened. After 940 new signs had already been installed across the New York City Subway system, mayor John Lindsay wrote a letter to the TA in an attempt to delay the planned route changes. Lindsay dropped his objection on November 22, just hours before workers started installing heavy equipment to reroute the tracks. Two days later, a New York state judge dismissed a lawsuit against the route changes. The opening of the Manhattan Bridge connection on November 26, 1967, was concurrent with the opening of the new express tracks on the Sixth Avenue Line between West Fourth Street–Washington Square and 34th Street, providing additional capacity for the extra trains on the IND via the connection. The following service changes were made, affecting about 200,000 passengers: The rush-hour only BB, which had run between Washington Heights–168th Street on the IND Eighth Avenue Line and 34th Street, was relabeled the B. It was extended via the new Sixth Avenue Line express tracks and the Chrystie Street Connection, then express on the BMT Fourth