Lollapalooza celebrates its 20th anniversary this year and to commemorate the occasion the festival has announced an eclectic mix of headliners including Eminem, Cee Lo Green and Nas.

The traditionally alternative festival appears to be breaking out of its comfort zone to help stay ahead of the game in the increasingly competitive summer festival market.

Cee Lo Green will take a break from opening for Rihanna for the date and Damian “Jr. Gong” Marley will join Nas for the headlining performance. Visit antiquiet for the full festival lineup.

This year's festival will take place August 5-7 at Grant Park in Chicago, IL.

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