Katy Perry and Rihanna Rock Hard at Rock in Rio Music Festival (Photos)

Brazil is the place to be this year. After the Miss Universe pageant which was hosted in Sao Paulo, about 100,000 people turned up on Friday for the Rock in Rio music festival in the city of Rio De Janeiro.

The event, which is the largest music festival in the world, is expected to attract 700,000 people over its week-long run.

The legendary Rock in Rio, which has been described as Brazil's Woodstock, is taking place in the City of Rock, a specially built venue on the future site of the Olympic Village when Rio hosts the 2016 Summer Games.

Best-selling artistes Katy Perry and Rihanna rocked the crowd at the festival.

After a stunning fireworks display and several local acts, Katy Perry kick started the event with her mega-hit Teenage Dream.

Hello Rio, Perry screamed to her cheering fans.

Rihanna also performed at the event's opening night. Clad in a red, white and black striped costume, the singer looked stunning and gave an amazing performance.

Elton John also performed on Friday.

Other artistes who will perform in the coming week include Lenny Kravitz, Stevie Wonder, the Red Hot Chili Peppers, Jamiroquai, Metallica, Maroon 5, Guns N' Roses, and top Brazilian singers such as Ivete Sangalo, reports AFP.

Around 1.4 million people attended the first edition of the Rock in Rio festival in 1985. A video of Queen performing Love of My Life in 1985 was shown at the start of Friday's concerts.

Check out some stunning pictures of Katy Perry and Rihanna perform at the Rock in Rio festival on Friday.