Illinois Facts, Stats and Information

Illinois Facts

  • U.S. State Name: Illinois
  • U.S. State Abbreviation: IL
  • U.S. Region: Midwestern United States
  • Admission to the Union: December 3rd, 1818
  • Total Area: 57,915 sq. mi.
  • Total Population: 12,812,508 (2020 USCB)
  • Capital City: Springfield, IL
  • Largest City: Chicago, IL

66 Illinois Facts

  1. Illinois is one of the 50 states of the United States of America.
  2. Illinois was the 21st state to join the United States on December 3, 1818.
  3. Illinois is in the midwestern region of the United States.
  4. Illinois is the 25th largest U.S. state, covering a total of 57,913.55 square miles or 1.52% of the total area of the United States.
  5. Illinois's 57,913.55 square miles is 95.87% land and 4.13% surface water.
  6. Illinois is ranked 25th with the most land area in the United States, with 55,518.93 square miles of land area.
  7. Illinois is ranked 19th with the most water area in the United States, with 2,394.62 square miles of water area.
  8. Illinois is the 6th most populated U.S. state with a population of 12,812,508 or 3.87% of the total population of the United States.
  9. The state capital of Illinois is the city of Springfield.
  10. Illinois is divided into 102 counties statewide.
  11. Cook County is the most populated county in Illinois
  12. The most populated city in Illinois is Chicago with an estimated 2,705,994 residents.
  13. The five most populated city in Illinois are Chicago, Aurora, Naperville, Joliet and Rockford.
  14. A native or resident Illinois is called a Illinoisan.
  15. Illinois's average elevation statewide is 600 feet.
  16. Illinois's highest elevation point is Charles Mound at 1,235 feet.
  17. Illinois's lowest elevation point is the Mississippi River at 279 feet.
  18. Illinois is all in the Central Time Zone (CT).
  19. The two letter abbreviation for Illinois is IL.
  20. The ISO 3166 code for Illinois is US-IL.
  21. Illinois is called the Prairie State and the Land of Lincoln.
  22. The estimated median household income in Illinois is $69,187.
  23. Illinois is the 30th most expensive U.S. state to buy a home with an estimated median home price of $202,675.
  24. Illinois is ranked 31st on the cost of living index out of all 50 U.S. states.
  25. Illinois has the 26th oldest population in the United States with a median age of 38.8.
  26. Illinois's average temperature is 51.37°F making it the 26th warmest state in the United States.
  27. Illinois on average has 38.52 inches of precipitation per year, making it the 30th wettest U.S. state.
  28. The hottest temperature ever recorded in Illinois was 117 °F on Wednesday, July 14, 1954, in East Saint Louis, IL.
  29. The coldest temperature ever recorded in Illinois was -38 °F on Thursday, January 31, 2019, in Mount Carroll, IL.
  30. Springfield is the third capital city of Illinois, prior to it becoming the permanent state capital city Vandalia and Kaskaskia were used to run the state government.
  31. The first U.S. state to ratify the 13th Amendment to the Constitution (slavery abolishment) was Illinois.
  32. The Home Insurance Building was the world’s first skyscraper, built in Chicago, Illinois between 1884 and 1885.
  33. The entire western border of Illinois follows the Mississippi River.
  34. Illinois generates more electricity from nuclear power plants than any other U.S. state.
  35. The oldest public zoo in the country is the Lincoln Park Zoo in Chicago, Illinois.
  36. In 1673, French explorers Jacques Marquette and Louis Jolliet become to first Europeans to explore modern-day Illinois.
  37. In 1779, trader Jean Baptiste Point du Sable settled in what is now modern-day Chicago, giving him the nickname “Founder of Chicago”.
  38. In 1814, the Illinois Herald is published in Kaskaskia, Illinois and becomes the first newspaper publication in the state.
  39. In 1830, Abraham Lincoln and his family move to Macon County, Illinois.
  40. In 1837, the City of Chicago is incorporated on March 4th and at the time was called the fastest growing city in the world.
  41. In 1855, the Illinois state government adopts a free public school system for all residents.
  42. In 1871, parts of the city of Chicago were devastated by a fire known as the Great Chicago Fire. The Great Chicago Fire started on October 8th and continue to devastate Chicago until October 10th. It’s estimated to have kill around 300 people and destroyed more than 17,000 buildings.
  43. In 1872, John Jones is elected as Cook County Commissioner, making him the first African-American elected to office in Illinois.
  44. In 1878, the Bell Telephone Company begins offering telephone services in Illinois.
  45. In 1890, the University of Chicago is established, and William Harper serves as the first president of the university.
  46. In 1909, a coal mine fire in Cherry, Illinois kills 259 people and today is the 3rd deadliest coal mining accident in the US.
  47. In 1913, women are granted the right to vote for President of the United States in Illinois.
  48. In 1925, the Tri-State Tornado hits southern Illinois and kills 613 people.
  49. In 1942, the world’s first self-sustaining nuclear chain reaction caused by humans occurs in Chicago, Illinois.
  50. In 1958, a fire breaks out at Our Lady of Angels School in Chicago, Illinois, killing 95 students and teachers. This tragic event resulted in massive changes to school fire safety across the United States.
  51. In 1974, the Sears Tower (today called the Willis Tower) in downtown Chicago is completed and becomes the tallest building in the world until 1998.
  52. In 1983, Harold Washington is elected mayor of Chicago and he becomes the first African-American of Chicago.
  53. In 1993, parts of Illinois are inundated with flood waters from the Great Flood of 1993.
  54. In 2000, Governor George H. Ryan bans executions in Illinois via a moratorium.
  55. In 2005, the Abraham Lincoln Presidential Museum opens in Springfield, Illinois.
  56. In 2008, Illinois bans smoking in virtually all public places, including offices.
  57. Civil engineer George Washington Gale Ferris Jr. was born in Galesburg, Illinois on February 14th, 1859. He is known for being the inventor of the original Ferris Wheel.
  58. Irish gangster John Patrick Looney was born in Ottawa, Illinois in 1865. He is infamous for being an Irish mob boss in Illinois during the early 20th century.
  59. Former United States President Ronald Regan was born in Tampico, Illinois on February 6th, 1911. He is famous for being elected the 40th President of the United States and served two terms between 1981 and 1989.
  60. Particle physicist James Cronin was born in Chicago, Illinois on September 29th, 1931. He is known was his experiment that proved that certain subatomic reactions do not adhere to fundamental symmetry principles. That experiment won him the 1980 Nobel Prize in Physics.
  61. Historian and author Stephen E. Ambrose was born in Lovington, Illinois on January 10th, 1936. He is famous for writing the book Band of Brothers, which was turned into a hit miniseries by HBO.
  62. Producer, screenwriter, and actor John Cusack was born in Evanston, Illinois on June 28th, 1966. He is famous for the various characters he has played in film, such as Con Air (1997) and Hot Tub Time Machine (2010).
  63. Illinois's official state motto is "State sovereignty, national union" .
  64. Illinois's official state bird is the Northern cardinal (Cardinalis cardinalis).
  65. Illinois's official state tree is the White Oak (Quercus alba).
  66. Illinois's official state flower is the Violet (Viola).

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Pictures of Illinois, USA

Illinois on a Map of the United States of America

The state of Illinois and its regional area on a Map of the United States of America.

The Official State Flag of Illinois

The official state flag of Illinois waving in the wind on a flag pole.

The Official State Seal of Illinois

The official state seal of Illinois that is used by the state's government.

Springfield the state capital of Illinois

Springfield the capital city of Illinois.

Chicago, Illinois, United States

Chicago, Illinois, United States of America.

Navy Pier In Chicago

Navy Pier In Chicago

Learn More About Illinois

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