How it all started
The largest festival in the world has only taken place four times, 1985, 1991 and 2001 and 2004. This year AOL Music brings you online live footage of the festival, as well as exclusive performances and backstage gossip.
Back in 1985 the stage was headlined by George Michael, Happy Mondays, INXS, A-Ha, Faith No More and New Kids on the Block - as well as three acts which appear again in 2006 - Santana and Guns n' Roses.
By 1991, the festival was broadcast live to 55 countries, and was watched by an incredible 580 million people.
2001 saw Britney Spears, Beck, Foo Fighters, Oasis, Red Hot Chili Peppers, REM and Sting take to the stage for Rock in Rio III. By then the festival had become a huge charity event - For a Better World - with some of the proceeds being given to Viva Rio Organization and other vocational education projects, led by organisations like UNESCO.
By 2004 the festival had relocated to Lisbon, Portugal, and included performances by Sir Paul McCartney and Sting.
Still in Lisbon, this year's Rock in Rio is five nights, across two weekends and will feature performances from some of the biggest names in rock and pop. Highlights will include Red Hot Chili Peppers, Roger Waters, Jamiroquai, Shakira, Anastacia, Sting and a re-united Guns n' Roses.
If you can't make it to Lisbon, don't worry; you can still enjoy the concert live and for free, with AOL Music. And if you miss the concert, come back over the next few weeks to watch each individual performance and highlights from all the acts, as well as exclusive backstage interviews, gossip and footage.