Mick Hartley

In 1936 Helen Levitt accompanied Walker Evans on a project to photograph passengers on the New York subway. Forty years later, around 1978, she returned, this time on her own, at a time when the subway was pretty much run down and dirty. She still concentrated on the passengers though, rather than the graffiti  - compare Richard Sandler's Eighties photos.

Some of the results have now been collected in a book, Manhattan Transit:

See here for some of Levitt's NYC 1940s street photography.