Aurora is a city in northeastern Illinois located along the Fox River. With a population of 180,542 as of the 2020 census, it is the second-most populous city in Illinois after Chicago and the 144th-most populous city in the United States. Aurora holds the distinction of being the most populous city in Illinois that is not a county seat.
The city's location in the Fox River valley has historically supported manufacturing and industrial development. Aurora's significant population makes it a major urban center in the Chicago metropolitan region, though it remains overshadowed by Chicago itself in terms of name recognition and economic influence.