Marking its 30-year anniversary at 2015's event, Rock in Rio has rocketed from a memorable 1985 show in Rio de Janeiro to a behemoth, week-long celebration of rock music (with a little pop, blues, rap and Música Popular Brasileira sprinkled in for good measure) with offshoots in three countries. In 1985, fresh from its dictatorial past, Brazil had never hosted a festival on this scale. Entrepreneur Roberto Medina changed that with the birth of Cidade do Rock , the City of Rock. This guy aimed big. Among the 28 bands at the first show? Think AC/DC, Iron Maiden, Ozzy Osbourne and Queen.