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Festival-goers were out in full force Thursday morning, some of whom slept on the street Wednesday night on Michigan Avenue in anticipation of the festival. The festival opens at 11 a.m. and closes at 10 p.m. each day. The city says it's prepared to welcome the crowds and keep them safe.
The four-day festival will feature eight stages with more than 170 bands, including an all-star lineup, starting with The Strokes and The Chainsmokers performing Thursday night.
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On Friday, Childish Gambino and Tame Impala take the stage and then on Saturday, it's Twenty One Pilots and Colombian singer J. Balvin. On Sunday, Ariana Grande and Flume close the festival.
"My friends and I, we were thinking of something spontaneous to do and we were like, 'We never been to Lollapalooza,' so we decided to come," said first-time Lolla-goer Jonathon Baillargeon.
For others, Lollapalooza is a tradition.
"This is my seventh year so some of our friends moved up here and we have made a trip every year to visit with them and hang out and come to the festival and see some music," said Ashley Markesbery, another attendee.
Security is always a top priority. Chicago police say both uniformed and plain clothes officers will be patrolling the area. In addition, more than 300 cameras and 900 private security guards will keep a close eye on Grant Park.
If you purchase a ticket, you agree to submit to a full body pat-down and to a screening by metal detector before entry.
"It's exactly like the airport, except you get to keep your shoes on," said Lolla-goer Emily O'Callahan.
"I am a huge fan of the extra security," said festival-goer Henry Lansing. "I have no problem with additional screening, longer lines if it means everyone is safe."
Organizers are telling wristband holders to be ready to have their bags checked; the official bag policy allows for small, single-pocket drawstring bags, empty hydration packs and small purses or fanny packs. Backpacks, bags with multiple pockets and any bag larger than 14 in. x 11 in. x 5 in. is prohibited and no exceptions will be made.
Anyone who refuses to comply with the search policy will be refused entry.
Festival organizers encourage attendees to use the buddy system and know where the exits are at all times.
Additional hydration stations are set up across the park, and while there is no extreme weather forecast for the next few days doctors are still urging caution and common sense.
About 280 people ended up at emergency rooms throughout the city in 2018, most often because of the combination of hot weather and alcohol consumption.
"If someone looks like maybe they are struggling a little bit, they've had a little too much fun, they're getting dehydrated, get them out of the heat, get them to a cooler area, to the shade, and get them something to drink," said Dr. Trevor Lewis of Cook County Hospital.
Even though the temperature forecast for this weekend is more moderate than last year, doctors emphasize the importance of taking breaks from the sun, wearing sunscreen and staying hydrated.