57 Interesting Illinois Facts That You Should Know

Last updated on February 7th, 2023

About Chicago 

1. Chicagoland is an informal term used for the entire Chicago metropolitan area.

2. Chicago was incorporated as a city in 1837.

3. Chicago is the county seat of Cook County.

4. Chicago is located on the shores of freshwater Lake Michigan.

Chicago on the map


5. Chicago is divided into 50 legislative districts or wards. An alderman who is elected by their constituency to serve a four year term represents each district.

6. Chicago has 77 community area and 100 neighborhoods.

7. Several nicknames are associated with Chicago including: Chi-Town, Second City, Windy City and the City of the Big Shoulders.

8. More lines of track radiate in more directions from Chicago than from any other city. Thus, Chicago is also referred as the Railroad Capital of the United States. Chicago stands second only to New York City in terms of the volume of commuter rail passengers carried each day. It is also the hub of Amtrak, the intercity rail passenger system.

9. Economically the city is one of the world’s most diverse and balanced, and according to some estimate, no single industry employs more than 14% of the workforce.

Chicago Skyline. facts about Chicago, Illinois.
Facts about Chicago, Illinois. Chicago’s Skyline. Image by Pedro Szekely

10. The Chicago area has one of the highest GDP’s in the world.

11. Chicago’s entire 28-mile Lake Michigan shoreline is man-made.

12. The world’s only drive-through post office is located in downtown Chicago. The Old Chicago Main Post Office, which is a nine-story building was built in 1921.   

Fun and interesting facts about Chicago

13. The world’s first successful open-heart surgery was performed on a human in 1893 by Dr. Daniel Hale Williams in Provident Hospital in Chicago. The patient took 51 days to recover from the wound.

the twinkie
Facts about Chicago, Illinois. A box of Twinkies. Image credit – Willis Lam

14. Did you know that the Twinkie was invented in Chicago in 1930? Since then it has become America’s favorite snack that were sold for five cents per package of two. Twinkie is a spongy cake filled with vanilla cream.    

15. The Wrigley Building was the first air-conditioned building in Chicago.

16. Spray paint was invented in Chicago.

17. Chicago is also one of the top most visited cities in the U.S. Domestic as well as international visitor flock to the city for its tourism friendly atmosphere and entertainment.

18. Commonly known as the “Founder of Chicago”, Jean Baptiste Point du Sable was the first known non-indigenous settler in Chicago.

19. Did you know that the world’s first controlled nuclear reaction was conducted at the University of Chicago on December 2, 1942, by physicist Enrico Fermi? The test was done as a part of the Manhattan Project.

20. In 1979, Jane Byrne became the city’s first female mayor.

21. Chicago is the Theatre capital of the U.S. The city has some 250 theatre companies and 200 theatres that keep the theatre-loving-mob entertained throughout the year. 

22. Did you know that the Chicago Park District which owns and manages more than 8,800 acres of green space, is the largest municipal park manager in the country. Some of the city’s famous recreational areas include: Jackson Park, Millennium Park, Lincoln Park, and Chicago Riverwalk.

23. Chicago has been dubbed the best restaurant city in America by Conde Nast Traveler.

About Chicago’s geography 

24. Chicago is home to 600 parks and 500 playgrounds. If you are a tennis enthusiast, you would be delighted to know that there are more than 500 tennis courts in the city. And the city also has plenty of fields for soccer and football.

25. The average height of Chicago city is 579 feet above mean sea level. 

26. In 2016, Bicycling Magazine named Chicago the best bicycle city in the U.S.

Bicycles in Chicago, Illinois, U.S.
Image credit – Marco Verch. Interesting Facts about Chicago. 

27. With more than 13,000 bike racks and 303 miles of bike lanes, Chicago has the second-highest percentage of commuters riding their bikes to work.

28. Did you know that Downtown Chicago has some double-decked and a few triple-decked streets? One such street is Wacker Drive. The street runs along the south side of the main branch and the east side of the south branch of the Chicago River in the Loop. Most of the street is double decked. The lower deck is used for through traffic and service vehicles; and the upper deck is used for local traffic and pleasure driving.    

29. The Chicago Loop which is one of Chicago’s 77 designated community areas is the second largest commercial district in North America. One can also call it Chicago’s commercial core. This is the area where you can find world’s renowned architectural feats including the Willis Tower, the AT&T Corporate Center, and the Chicago Board of Trade Building.

About Chicago’s history

30. In 1848, a couple of important things happened to the city. One was the opening of Chicago’s first railway, Galena and Chicago Union Railroad; and the other was the opening of the Illinois and Michigan Canal.

31. The construction of the Illinois and Michigan Canal transformed the fate of Chicago. On April 24, 1848, the first cargo boat arrived in Chicago by canal. The canal and later the railroads made Chicago an attractive location for manufacture. 

32. Did you know that, founded in 1871, the Chicago Tribune is the largest newspaper in the Midwest? The newspaper which is a part of the Tribune Publishing Company, is headquartered in Chicago, Illinois.

33. The Chicago Convention which is also known as the Convention on International Civil Aviation established the International Civil Aviation Organization (ICAO). ICAO is a specialized agency which coordinates and regulates international air travel. The Convention was signed by 52 states on 7 December 1944 in Chicago, Illinois, U.S., and came into effect on 4 April 1947.

34. According to the Chicago State University, its graduates earn an average of $44,000 upon graduation.

35. The Pilsen Historic District was named by the Czech immigrants after Plzen, the fourth largest city in the Czech Republic.

36. Did you know that in 1837, the first hospital blood bank in the United States was established at Cook County Hospital in Chicago? Dr Bernard Fantus coined the term “blood bank”. Interestingly, it was the Austrian physician who first grouped blood into types A, B and O. It was during the First World War that direct human to human blood transfusion was done, which saved many lives.

Chicago – quick facts and statistics

State nameIllinois
Population2,694,236 (2020)
AreaCity: 227.63 sq mi

Water: 6.80 sq mi
CountiesCook, DuPage
GovernmentType: Mayor–council
Body: Chicago City Council
MayorLori Lightfoot (D)
(Assumed office on May 20, 2019)
Settledcirca 1780
Date of IncorporationMarch 4, 1837
Major IndustriesManufacturing, printing and publishing, finance and insurance, and food processing.
Zip codes606xx, 607xx, 608xx
Table last updated30 May, 2020