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Lollapalooza, Chicago's most popular summer music festival, has officially started on August 3, 2012 and will continue through August 5, 2012. This year the festival, located in Grant Park, celebrates its 20th anniversary by giving supporters, what fans are saying, one of the best concert line ups in years. Tickets for the festival are completely sold out!
(WLS Photo / Evan Peterson/ ABC 7 Chicago)