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A Division (New York City Subway)

A Division
Technical
Track gauge 4 ft 8 12 in (1,435 mm)
Minimum radius 147.25 ft (44.88 m)

The A Division, also known as the IRT Division, is a division of the New York City Subway, consisting of the lines operated with services designated by numbers (1, 2, 3, 4, 5, 6, 7) and the 42nd Street Shuttle. These lines and services were operated by the Interborough Rapid Transit Company before the 1940 city takeover. A Division cars are narrower, shorter, and lighter than those of the B Division, measuring 8.6 by 51 ft (2.6 by 15.5 m).

The following lines are part of the A Division (services shown in parentheses; lines with colors next to them are trunk lines):

Numbers were assigned to subway services in 1948:

The 42nd Street Shuttle and Bowling Green – South Ferry Shuttle also provided subway services, and elevated service remained on the Third Avenue Line and Polo Grounds Shuttle.


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