The K once ran along the C line in Manhattan, but the letter was retired in 1988.

Once a letter disappears from the map, that doesn’t mean it is gone forever. The W train, between Queens and Manhattan, was axed in 2010 and then reappeared in 2016 as part of new service after the opening of the Second Avenue subway, which diverted the Q train to three new stations on Manhattan’s Upper East Side.

As for the Z, transit advocates held a funeral for the line amid budget cuts in 2009, but it has survived after all (for now).



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