Tinley Park is a village in Cook County, Illinois, (with a small portion in Will County), and is a suburb of Chicago. Per the 2020 census, the population was 55,971 and it is among the fastest-growing suburbs southwest of Chicago. In 2009, BusinessWeek named Tinley Park the "best place in America" to raise a family. Since its opening in 1990, Tinley has been the home to the Hollywood Casino Amphitheatre (formerly World Music Theater, Tweeter Center Chicago and First Midwest Bank Amphitheatre) music venue, accommodating around 28,000 people.