Rockford was first established in 1834-1835 on the east and west banks of the Rock River in the far northern area of Illinois. Nicknamed the “Forest City,” Rockford is the county seat of Winnebago County. As of the 2000 census, Rockford had just over 150,000 residents, making it the second most populous city in Illinois (not counting Aurora, a large suburb of Chicago.) The greater metropolitan area surrounding Rockford is comprised of close to 340,000 people.