DuPage County, Illinois in the context of Itasca, Illinois

O'Hare, located on the far north side of Chicago, is one of the city's 77 community areas. O'Hare International Airport is located within the boundaries of this community area. This community area is the only one that extends outside Cook County; the western edge (an area comprising the southwest part of the airport) is in DuPage County.

The area is a transportation hub containing O'Hare International Airport as well as major roads such as Interstate 90, its auxiliary Interstate 190, Interstate 294, Illinois Route 72, Illinois Route 171, U.S. Route 12 and U.S. Route 45. This allows the O'Hare neighborhood, combined with the nearby suburb of Rosemont, to work as an edge city.

Lombard is a village in DuPage County, Illinois, United States, and a suburb of Chicago. The population was 44,476 at the 2020 census.

Wheaton is a city in and the county seat of DuPage County, Illinois, United States. It is located in Milton and Winfield Townships, approximately 25 miles (40 km) west of Chicago. As of the 2020 census, Wheaton's population was 53,970, making it the 27th-most populous municipality in the state.

West Chicago is a city in DuPage County, Illinois, United States. The population was 25,614 at the 2020 census. It was formerly named Junction and later Turner, after its founder, John Bice Turner, president of the Galena and Chicago Union Railroad (G&CU) in 1855. The city was initially established around the first junction of railroad lines in Illinois, and today is still served by the Union Pacific West Metra service via West Chicago station.

Interstate 55 (I-55) is a major north–south Interstate Highway in the US state of Illinois that connects St. Louis, Missouri, to the Chicago metropolitan area. It enters the state from Missouri near East St. Louis, Illinois, and runs to U.S. Route 41 (US 41, Lake Shore Drive) near Downtown Chicago, where the highway ends, a distance of 294.38 miles (473.76 km). The road also runs through the Illinois cities of Springfield, Bloomington, and Joliet. The section in Cook County is officially named the Stevenson Expressway for the governor, and in DuPage County it's officially named the Joliet Freeway or the Will Rogers Freeway for the humorist. The section from the south suburbs to the area near Pontiac is officially named the Barack Obama Presidential Expressway after the president, who launched his political career from Illinois.

Schaumburg (/ˈʃɔːmbɜːrɡ/ SHAWM-burg) is a village in Cook and DuPage counties in the U.S. state of Illinois. At the 2020 census, the population was 78,723, making Schaumburg the most populous incorporated village in the United States. Schaumburg is around 26 miles (42 km) northwest of downtown Chicago and 10 miles (16 km) northwest of O'Hare International Airport. It is part of the Golden Corridor.

Schaumburg's transition from a rural community to a suburban city began with Alfred Campanelli's first large-scale suburban-style development in 1959 and Woodfield Mall's opening in 1971. Schaumburg is bordered by Hoffman Estates and Palatine to the north, Inverness in northwest, Rolling Meadows to the northeast, Elk Grove Village to the southeast, Roselle to the south, Hanover Park to the southwest, and Streamwood to the west.

The Presbytery of Chicago is a regional governing body of the Presbyterian Church (USA), encompassing congregations and ministries within Cook, Lake, and DuPage counties in northeastern Illinois. It is headquartered at Northwest Point, 25 NW Point Blvd., Elk Grove Village, Illinois.

The Valparaiso Moraine is a recessional moraine (a landform left by receding glaciers) that forms an immense U around the southern Lake Michigan basin in North America. It is a band of hilly terrain composed of glacial till and sand. The Valparaiso Moraine defines part of the continental divide known as the Saint Lawrence River Divide, bounding the Great Lakes Basin. It begins near the border of Wisconsin and Illinois and extends south through Lake, McHenry, Cook, DuPage and Will counties in Illinois, and then turns southeast, going through northwestern Indiana. From this point, the moraine curves northeast through Lake, Porter, and LaPorte counties of Indiana into Michigan. It continues into Michigan as far as Montcalm County.

The moraine was formed during the Crown Point Phase of the Wisconsin glaciation. At this time the glacier covering the area had grown thin, so it was restrained by dolomite rock layers in the Lake Michigan basin. Where the glacier stopped, glacial till and sand was deposited, creating the hills of the moraine. After the Valparaiso Moraine was formed, the glacier retreated and formed the Tinley Moraine.

Naperville (/ˈneɪ.pər.vɪl/, NAY-pər-vil) is a city in DuPage and Will counties in the U.S. state of Illinois. It is a city southwest of Chicago located 28 miles (45 km) west of the city on the DuPage River. As of the 2020 census, its population was 149,540, making it the state's fourth-most populous city.

Naperville was founded in 1831 by Joseph Naper. The city was established by the banks of the DuPage River and was originally known as Naper's Settlement. By 1832, over 100 residents lived in Naper's Settlement. In 1839, after DuPage County was split from Cook County, Naperville became the county seat, which it remained until 1868. Beginning in the 1960s, Naperville experienced a significant population increase as a result of Chicago's urban sprawl.