These lines were conceived as part of the Metropolitan Transportation Authority (MTA)'s 1968 expansion plans, and along with the 63rd Street lines and a small section of the Second Avenue Subway, they were the only portions of the plan to be completed before it was scaled back due to fiscal issues. These lines were originally planned to be extended further east into Queens. Construction on the line started in 1973, and the project was expected to be completed in 1980. However, due to financial issues and concern about the quality of the construction, the lines did not open until December 11, 1988. On that date, several bus routes serving the 169th Street station were diverted to the new bus terminal at Jamaica Center. This line is also used by passengers transferring to or from the Long Island Rail Road and the AirTrain JFK.