Other cities in the 630 area code include: Downers Grove, Lombard, Bartlett, Wheeling, Northbrook, Elk Grove Village, Oswego, Glen Ellyn, West Chicago, Maywood, Geneva, Yorkville, Lemont, La Grange, Wood Dale, La Grange Park, Warrenville, Plano, Summit Argo, Sugar Grove, Itasca, Elburn, Big Rock, Aurora, Batavia, Bensenville, Bolingbrook, Elgin, Elmhurst, Hinsdale, Oak Brook, Roselle, and Saint Charles.
Chicago, officially the City of Chicago, is the third-most populous city in the United States. With over 2.7 million residents, it is the most populous city in the state of Illinois, and the Midwestern United States. It is the county seat of Cook County. The Chicago metropolitan area, often referred to as Chicagoland, has nearly 10 million people and is the third-largest in the U.S. Chicago is called the architecture capital of the United States. In terms of wealth and economy, Chicago is considered one of the most important business centers in the world. Chicago was incorporated as a city in 1837, near a portage between the Great Lakes and the Mississippi River watershed, and grew rapidly in the mid-nineteenth century. Positioned along Lake Michigan, the city is an international hub for finance, commerce, industry, technology, telecommunications, and transportation: O'Hare International Airport is the second- busiest airport in the world when measured by aircraft traffic ; the region also has the largest number of U.S. highways and rail road freight. In 2012, Chicago was listed as an alpha global city by the Globalization and World Cities Research Network, and ranked seventh in the world in the 2016 Global Cities Index. Chicago has the third-largest gross metropolitan product in the United States—about $640 billion according to 2015 estimates. The city has one of the world's largest and most diversified economies with no single industry employing more than 14% of the workforce. In 2016, Chicago hosted over 54 million domestic and international visitors, a new record making it one of the top visited cities in the nation. Landmarks in the city include Millennium Park, Navy Pier, the Magnificent Mile, Art Institute of Chicago, Museum Campus, the Willis (Sears) Tower, Museum of Science and Industry, and Lincoln Park Zoo. Chicago's culture includes the visual arts, novels, film, theater, especially improvisational comedy, and music, particularly jazz, blues, soul, hip hop, gospel and house music. There are many colleges and universities in the Chicago area; among these, Northwestern University, University of Chicago, and the University of Illinois at Chicago are classified as "highest research" doctoral universities. Chicago also has professional sports teams in each of the major professional leagues. The city has many nicknames, the best-known being the Windy City.
Naperville is a city in DuPage and Will counties in the U.S. state of Illinois, and a suburb of Chicago. Naperville was voted the second-best place to live in the United States by Money magazine in 2006. It was rated 1st on the list of best cities for early retirement in 2013 by Kiplinger. In a 2010 study, Naperville was named the wealthiest city in the Midwest and eleventh in the nation with a population over 75,000. It was ranked among the nation's safest cities by USAToday and Business Insider. As of the 2010 census, the city had a population of 141,853, which was estimated to have increased to 147,100 by July 2015. It is the fifth-largest city in Illinois.
Arlington Heights is a town in Cook County in the U.S. state of Illinois. A suburb of Chicago, it lies about 25 miles (40 km) northwest of the city's downtown. The population was 75,101 at the 2010 census. It is the most populous community in the United States that is incorporated as a "village", although it is not far ahead of its nearby Illinois neighboring villages of Schaumburg and Bolingbrook and adjacent Palatine.Arlington Heights is known for Arlington Park Race Track, home of the Arlington Million, a Breeders' Cup qualifying event; it also hosted the Breeders' Cup Classic in 2002. The village is also home to the Arlington Heights Memorial Library, which has one of the largest collections in the state.
The 630 area code lies within the Central Daylight Time Zone (or CDT). The current time in Central Daylight Time is 1:50 PM on Apr 20, 2021.