First Midwest Bank Amphitheatre is a music venue in Tinley Park, IL that opened in 1990. Tinley Park is a village located primarily in Cook County, Illinois, United States with a small portion in Will County. Year 1990 ( MCMXC) was a Common year starting on Monday (link displays the 1990 Gregorian calendar) It is one of the largest music venues in the Chicago area with capacities up to 28,000 spectators. The facility was formerly named Tweeter Center Chicago, World Music Theater and New World Music Theater.