The NFL is holding an event at Chicago’s Grant Park to celebrate the start of the 100th season. The kickoff celebration will feature a series of free concerts and a watch party for the Bears-Packers game tonight at Soldier Field. Shows by Meek Mill and Meghan Trainor highlight the pregame events near Buckingham Fountain. Fans will be able to get autographs from Bears greats Richard Dent, Charles Tillman, Matt Forte and Jim McMahon.