The putrid smell of an (almost) empty subway car is still with us, but New York City's underground transit system is a lot more cleaned up than it used to be. Now, a subway car is more likely to be covered in Target ads than graffiti.

PHOTOS: NYC graffiti artist creates anti-ISIS subway mural

Lauded photographers Martha Cooper and Henry Chalfant made a name for themselves documenting New York City's graffiti culture in the 1970s and 1980s. Their 1984 book "Subway Art" has been celebrated for documenting an important part of hip hop history and the graffiti movement. For the book's 25th anniversary, the book has been updated with 70 new photos, not included in the original release. We highlight a few here.

Related: Exploring "New York's Underground Art Museum"

Henry Chalfant and graffiti writer Crash are hosting an event at the 92nd St. Y celebrating the book on Jan. 28 at noon. Get all the details here.

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