30. Houston Bowery Mural by Retna, 2012
Retna a.k.a. Marquis Lewis has invented a now well-known alphabetic script, influenced by Egyptian hieroglyphs, graffiti, and calligraphy. Retna's unmistakable script is not just a pretty pattern—most works can be decoded by those in the know. This particular mural reads, "Watch the heartbeat of your wrist/a precise pulsing beat/of Life's drum. With a loss of timing, you are ill." The Houston Bowery Mural location has a long history with street art; work from artists such as Keith Haring, Os Gemeos, Barry McGee, and Shepard Fairey have donned the same wall in the past, making Retna's work a special piece defining the contemporary moment.