There are 472 stations in the NYC Subway system (which is controlled by the State Governor). The stations are a mixture of underground, elevated, embankment, or open-cut stations. Riders need stairs to access the concourse and platforms.
I find the context around the stairs more interesting than the stairs themselves: a microcosm of New York City at each stair.
These are examples of Sub ianua (train steps) from Manhattan, Brooklyn, and Queens. Often bollards are found nearby, as are post office boxes, Rota custodia (CityRack), Rota custodulus (Mini CityRack), and Sub operimentum (MTA subway sidewalk grate).
Court Square E/M/G/7 Station stair. 
World Trade Center 
Chambers Street Subway entrance 
World Trade Center 
7 train subway entrance 
72nd St head house 
Jackson Ave Elevated 
207th St Station
