Lollapalooza's biggest ever festival underway in Grant Park
Chicago's Grant Park will be covered with screaming music fans for the next three days.

WGN's Dean Richards says Coldplay seems to be the main attraction for the crowds today.

270,000 people are expected to attend the three day Lollapalooza.

The 20th anniversary edition features 130 acts, on eight stages, including headliners Eminem, The Foo Fighters, Muse, and Coldplay.

Mass transportation is highly recommended for anyone who's going.

Not only will there be massive crowds in the downtown area for Lollapalooza, but there will also be crowds expected at events at televangelist Joel Osteen's event at U.S. Cellular Field, Bears Family Night at Soldier Field, and Sade and John Legend are performing at the United Center.

The CTA says it will have extra trains and buses in service.

Metra is also planning to have additional trains in service.

Drivers will also have to maneuver around several street closures.

Columbus Drive is closed from Monroe to Roosevelt.

Congress Parkway is closed from Michigan Avenue to Columbus.

Balbo and Jackson Drives are both closed from Michigan to Lake Shore Drive.