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Change The World By Going To This Chainsmokers Concert — Yes, Really

Global Citizen Festival reveals its star-studded lineup

Music festivals aren't just for the summer. The annual Global Citizen Festival will take over New York City's Central Park on September 23 — one day after autumn officially begins. Headliners were announced Tuesday (August 1), and man, this is one show you don't want to miss.

The Chainsmokers will be taking the stage, and the rest of the headlining performances are equally exciting: Green Day, The Killers, The Lumineers, and — last but certainly not least — the legendary Stevie Wonder. Plus, special guests Pharrell Williams, Big Sean, Alessia Cara, and Andra Day will be attending. But wait, it gets even better!

The festival is 100 percent free. Yep, you read that right. Here's how you can go.

To score two free tickets, download the Global Citizen app and participate in various "actions" that'll help change the world one step at a time. Examples include calling a member of Congress or tweeting at world leaders asking them to improve education and health care in their respective countries. For every action you complete, you get points. Once you collect enough points, you're entered into a lottery to win a pair of tickets. Easy peasy.

These small actions add up to something far bigger, however. Last year, the 60,000 people who attended the Global Citizen Festival reached over 199 million people with their efforts. For more info, visit the Global Citizen website.