The festival will take place July 29 to Aug. 1.
Miley Cyrus will headline Thursday night, with Tyler the Creator and Marshmello on Friday, Post Malone, Megan Thee Stallion and Journey on Saturday and Foo Fighters and DaBaby on Sunday.
Single-day tickets go on sale at noon at www.lollapalooza.com.
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In accordance with current local public health guidance, full COVID-19 vaccination or negative COVID-19 test results will be required to attend Lollapalooza 2021. For patrons who are not fully vaccinated, a negative COVID-19 test result must be obtained within 24 hours of attending Lollapalooza each day.
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The festival will be at full capacity. In 2019, it drew 400,000 people to the park over four days.
How fans will prove they've been vaccinated is still in the works, but it could involve mobile apps, or showing your vaccination card. Details on the festival entry process will be available in early July, organizers said.