Chicagoland is a region in northeastern Illinois, including Chicago and its surrounding suburbs. By some definitions, Chicagoland also includes parts of Southeast Wisconsin and Northern Indiana.
The major cities of the region are, well, Chicago — period. None of the outlying cities remotely approach the size of this mammoth metropolis. But that's not to say that Chicagoland doesn't include other cities; other large ones include:
Cook County, where Chicago is located, is the largest county in Illinois and the second-largest in the United States (after California's L.A. County). With more than 5 million residents, its population is larger than that of most U.S. states; a little more than half of them live in the central city, with the rest in a chain of suburbs that surrounds Chicago on the north, west and south sides.
Evanston, the first city north of Chicago along the lake, is home to Northwestern University. Other communities along Cook County's affluent North Shore are Skokie, Wilmette, Winnetka and Glencoe, with towns like Morton Grove and Glenview further inland.
To the northwest of Chicago, in the vicinity of O'Hare International Airport, are such towns as Des Plaines, Arlington Heights, Niles and Park Ridge.
Cook County's West Side includes towns like Oak Park, Berwyn
To the south are such communities as Blue Island, Chicago Heights and Harvey.
West of Cook County, DuPage contains mainly Chicago bedroom communities, such as Glen Ellyn, Naperville, Itasca and
Lake County, in the northeast corner of the state, was once largely rural but has become increasingly suburban in recent years. Its largest city, Waukegan, is also the county seat. Its southeast is part of Chicago's affluent North Shore, including Highland Park and Lake Forest, one of the wealthiest communities in the state. Other Lake County towns include Libertyville, Gurnee, Buffalo Grove, Fox Lake and Long Grove.
Will County lies south of Cook and DuPage; its largest city and county seat is Joliet.
- The Chicago Tribune  ("The Trib") is the Chicago area's biggest daily, and publishes a suburban edition.
- The Daily Herald  is a large daily newspaper aimed primarily at the suburbs.
- The Northwest Herald.
- O'Hare International Airport, one of the largest and busiest in the world, is located in the northwest Chicagoland area.
- Midway Airport is a smaller airport on the South Side of Chicago.
Chicagoland is served by numerous Amtrak routes.
In addition to an extensive highway system, Chicagoland is served by Metra's 12 rail lines and by Chicago's CTA, which reaches some of the nearer suburbs.
- The Baha'i Temple, a cultural and architectural wonder in Wilmette.
- The beautiful Chicago Botanic Garden in Glencoe.
- Frank Lloyd Wright House and several houses designed by the architect in Oak Park.
- The Kohl's Children's Museum in Glenview.
- The splendid Morton Arboretum in Lisle.
- The Joliet Correctional Facility, Illinois' most notorious prison, in Joliet.
- The Forest Preserve District of Cook County  is responsible for the numerous open spaces ("forest preserves") around the county. These preserves range from heavily used parks with extensive roads and well-developed picnic areas, to relatively isolated expanses of land that are only really accessible on foot (or cross-country skis in Winter).
- The Pickwick in Park Ridge is one of the true grand movie palaces remaining in the Chicagoland area.
- Illinois Beach State Park in Zion.
- The Six Flags Great America amusement park in Gurnee.
- The Empress and Harrah's casinos in Joliet.
- The Chicagoland Speedway in Joliet
Chicagoland is adjacent to Northern and Central Illinois, to Southeast Wisconsin, and to Northern Indiana. Parts of Wisconsin and Indiana are sometimes included in the definition of Chicagoland.
Wikipedia:Chicago metropolitan area