Lollapalooza, one of the largest music festivals in the United States, has drawn around 100,000 people to Chicago, and most have come from far-flung states or countries.
"Only about 20 percent of ticket holders are coming from inside Chicago," Lindsay Hoffman, Lollapalooza's marketing manager, told ABC News Chicago. "Eighty-percent are coming from outside, 11 percent internationally."
Lollapalooza is a weekend-long concert series that has taken over Chicago's Grant Park for the past eight years, after starting as a traveling show 21 years ago, USA Today reported.
"Lollapalooza remains the grand poobah of late-summer American festivals," wrote Billboard of the event.
This year, the festival sold out of tickets, welcoming 10,000 more concert-goers than they saw in 2011, according to USA Today.
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"We're taking the city, and we're filling the arteries of the city and its nightclubs and ballrooms with our Lollapalooza audience and musicians," the concert's founder Perry Farrell, who is also the frontman for alternative rock band Jane's Addiction, told CNN. "We're taking it up a notch, and we're taking it to four in the morning," he said.
"It's not just Grant Park," he added. "The whole city is alive!"
This year's line-up includes The Shins, the Black Keys, Metric, Wale, and a Black Sabbath reunion show, music blog Spinner reported.
British singer-songwriter Michael Kiwanuka, who played a set on Friday, told Rolling Stone that though he was disappointed to be away from his home turf during the Olympics, Lollapalooza wasn't a bad alternative.
"When you get to play Lollapalooza in the sun, it's a pretty cool substitute," Kiwanuka said.
"What I want to see grow is (for the fest's) tentacles to extend out to the city and more things going on outside after," founder Farrell told USA Today. "People have come from around the globe, 11 percent of our audience now is international, so they're here and they're young."
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