New York City Transit
A Division
The A division is the IRT lines (numbered lines) and are 1 foot narrower and 9-24 feet shorter than their B division counterparts and have only three sets of doors per side rather than four sets per side. The IRT was built by August Belmont who wanted no freight service on “his railroad” and designed smaller clearances to ensure no freight trains. To this date, A and B division cars are separate and only A division cars are operable (ignoring the wide gap) on either A or B Division tracks and then only with adjustments or special procedures.
There are three interconnections between the A and B division:
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from the Jerome Avenue Line through Jerome and Concourse Yards to the Concourse line. |
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Full diamond crossover at Queensboro Plaza (thanks to former dual BMT/IRT operation of Astoria line (Now BMT) and Corona Line (Now IRT) |
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From the New Lots Line center track at Junius Street to the Linden Yards and Canarsie Line (no Third rail) |
Except for portions “inherited” from old elevated lines, the IRT is the oldest of the three subway divisions and most of those have been demolished or heavily rehabilitated.
S Train (Times Square/ Grand Central Shuttle)