New York City Subway
Guerrilla art

The New York City Subway system has been a target for unauthorized or "guerrilla" art since the 1970s, beginning with graffiti and tagging. Originally thought of as vandalism, the art form eventually emerged as an authoritative typology in the 1980s, especially with the release of the 1983 documentary Style Wars. Prominent pop-artist Keith Haring got his start tagging blank billboards on subway platforms with chalk art. In 2019–2020, the Bronx Museum mounted an exhibition of graffiti-tagged subway cars.

More contemporary installations have taken place as well. In 2014, artist London Kaye yarn-bombed the L train, wrapping metal hand poles in knit fabric. In 2019, artist Ian Callender used projectors to show accurate views of the cityscape above moving 6 trains on the ceilings of entire cars. In 2021, illustrator Devon Rodriguez went viral for his drawings of fellow commuters.
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