Being relatively close to both I-80 and I-55, Chicagoland Speedway is easily accessible and less than an hour in travel time from downtown Chicago.
In the first years of the track's existence when buying the four race ticket package (2 NASCAR / 2 IndyCar) was required, the place was packed for the Cup race.
Eventually, even though the four race ticket requirement was done away with, the size of the crowds diminished somewhat but at the last Cup race there in 2019 the grandstands were full.
Chicago area race fans didn't give up on Chicagoland Speedway, NASCAR did.