Illinois, one of the Midwestern states of the United States. It is bounded by Wisconsin, Indiana, Kentucky, Missouri, and Iowa. Lake Michigan forms part of the eastern boundary. Illinois is the 25th largest state, with an area of 57,918 square miles (150,007 km2).

The state bird of IllinoisThe state bird of Illinois is the cardinal.
Illinois in brief
General information
Statehood: Dec. 3, 1818, the 21st state.
State abbreviations: Ill. (traditional); IL (postal).
State capital: Springfield, the capital of Illinois since 1839. Earlier capitals were Kaskaskia (1818-1820) and Vandalia (1820-1839).
State motto: State Sovereignty, National Union.
Popular name: The Land of Lincoln.
State song: "Illinois." Words by Charles H. Chamberlin; sung to the tune of "Baby Mine" by Archibald Johnston.
Symbols of Illinois
State bird: Cardinal.
State flower: Violet.
State tree: White oak.
State flag and seal: Illinois's state flag, first adopted in 1915, bears the state seal on a white background. A 1970 statute added the name Illinois and ensured uniformity in design. On the seal, adopted in 1868, a bald eagle holds a shield with stars and stripes that represent the original 13 states. The laurel leaves symbolize the great achievements of Illinois citizens. The sun rising over the prairie stands for the progress made since statehood and for the future.
Land and climate
Area: 56,343 mi2 (145,928 km2), including 750 mi2 (1,941 km2) of inland water but excluding 1,575 mi2 (4,079 km2) of Great Lakes water.
Elevation: Highest--Charles Mound, 1,235 ft (376 m) above sea level. Lowest--279 ft (85 m) above sea level along the Mississippi River in Alexander County.
Record high temperature: 117 °F (47 °C) at East St. Louis on July 14, 1954.
Record low temperature: –36 °F (–38 °C) at Congerville on Jan. 5, 1999.
Average July temperature: 76 °F (24 °C).
Average January temperature: 26 °F (–3 °C).
Average yearly precipitation: 38 in (97 cm).
Population: 12,419,293.
Rank among the states: 5th.
Density: 220 per mi2 (85 per km2), U.S. average 78 per mi2 (30 per km2).
Distribution: 88 percent urban, 12 percent rural.
Largest cities in Illinois: Chicago (2,896,016); Rockford (150,115); Aurora (142,990); Naperville (128,358); Peoria (112,936); Springfield (111,454).
Chief products
Agriculture: beef cattle, corn, greenhouse and nursery products, hogs, milk, soybeans, wheat.
Manufacturing: chemicals, fabricated metal products, machinery, printed materials, plastics and rubber products, processed foods and beverages.
Mining: coal, crushed stone, petroleum, sand and gravel.
State government
Governor: 4-year term.
State senators: 59; 2- or 4-year terms.
State representatives: 118; 2-year terms.
Counties: 102.
Federal government
United States senators: 2.
United States representatives: 19.
Electoral votes: 21.
Sources of information
For information about tourism, write to: Illinois Department of Commerce and Economic Opportunity, Illinois Bureau of Tourism, 100 W. Randolph Street, Suite 3-400, Chicago, IL 60601. The Web site at also provides information.
For information on the economy, write to: Illinois Department of Commerce and Economic Opportunity, 100 W. Randolph Street, Suite 3-400, Chicago, IL 60601.
The state's official Web site at also provides a gateway to much information on Illinois's economy, government, and history.
For information about the state's history, write to: Illinois Historic Preservation Agency, Old State Capitol, Springfield, IL 62701.