Paul McCartney, Metallica, Florence and the Machine, Sam Smith, and Kaskade were among the headliners.
On Sunday afternoon, the festival was briefly evacuated as a storm moved in, but music resumed after a 90-minute delay. The weather returned later that evening just in time for Florence and the Machine to close out the festival amid a lightening storm.
A record-tying 300,000 fans descended upon Grant Park in Chicago this weekend to watch over 150 musicians perform.
Of Monster and Men performed before the weather got bad on Sunday, forcing a 90-minute delay for afternoon shows.
Florence and the Machine closed out the festival on Sunday night amidst a beautiful lightening storm, but were forced to end 30 minutes early as severe weather moved over Chicago.
Lead singer Florence Welch got so into her performance that she ripped off her top and ran through the pit wearing just her bra. Fans caught the moment on video (5:10).
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