Illinois
IL · Data from 2022–2023 government sources
Illinois, the Prairie State, sits at the crossroads of America — geographically, culturally, and economically. Chicago, the nation's third-largest city, is a global center of finance, architecture, and culture. But Illinois extends far beyond its famous metropolis, encompassing rich farmland in the central plains, historic river towns along the Mississippi, and the rolling hills of the Shawnee National Forest in the south.
Think you know Illinois? Test your geography skills.
Play GeoProwlHistory
Illinois takes its name from the Illini confederacy of Native American tribes. French explorers Marquette and Joliet were among the first Europeans to traverse the region in 1673. Illinois became the 21st state on December 3, 1818. Abraham Lincoln, the 16th president, began his political career in Springfield, which remains the state capital. The Great Chicago Fire of 1871 destroyed much of the city but led to an unprecedented building boom that made Chicago a laboratory for modern architecture.
Economy
Illinois has a GDP exceeding $1 trillion, making it one of the largest state economies. Chicago is a global financial center, home to the Chicago Mercantile Exchange and the Chicago Board of Trade. The state is a transportation hub — O'Hare International Airport is one of the busiest in the world, and more freight rail passes through Chicago than any other U.S. city. Agriculture is enormous: Illinois ranks first or second nationally in soybean and corn production. Manufacturing, healthcare, and technology round out the diversified economy.
Geography & Landmarks
Illinois covers 57,914 square miles, stretching 390 miles from the Wisconsin border to the southern tip where the Ohio and Mississippi Rivers converge. The northern third features the Chicago metro and glacially flattened prairie. Central Illinois is quintessential Midwest farmland — some of the most fertile soil on Earth. Southern Illinois, known as 'Little Egypt,' is hilly and forested, with the Shawnee National Forest offering dramatic bluffs, canyons, and the Garden of the Gods. The Cache River wetlands in southern Illinois contain some of the oldest trees east of the Mississippi, including bald cypresses over 1,000 years old. Starved Rock State Park along the Illinois River features 18 canyons carved by glacial meltwater, with waterfalls that are most spectacular during spring snowmelt.
Emmett Till and Mamie Till-Mobley National Monument — NAACP Records, Prints and Photographs Division, Library of Congress
Source: NPS API
Culture & Traditions
Illinois is a cultural colossus, with Chicago serving as the birthplace of Chicago blues (made electric by Muddy Waters and Howlin' Wolf), the Chicago house music scene of the 1980s, and improv comedy through The Second City, which launched the careers of Bill Murray, Tina Fey, and Stephen Colbert. Chicago's deep-dish pizza, invented at Pizzeria Uno in 1943, and the Italian beef sandwich are culinary institutions, while the Chicago-style hot dog (no ketchup) is an article of local faith. The Art Institute of Chicago houses world-class collections including Seurat's A Sunday Afternoon on the Island of La Grande Jatte and Grant Wood's American Gothic. The state's sports culture is legendary, with the Chicago Bears (founding NFL franchise, 1920), the Bulls' dynasty under Michael Jordan, and the Cubs' 2016 World Series victory ending a 108-year championship drought.
Notable Cities
Springfield
CapitalThe state capital and Abraham Lincoln's adopted hometown. The Lincoln Presidential Library and Museum, Lincoln's Tomb, and the Old State Capitol are major historic sites.
114,214
Population
$62,419
Median income
$147,700
Home value
$913
Median rent
40.1
Median age
6.6%
Unemployment
62.4%
Homeownership
15,999
Bachelor's+
Chicago
The third-largest city in the U.S. and a global metropolis known for deep-dish pizza, blues and jazz music, world-class museums, and a stunning lakefront skyline.
Rockford
Illinois's third-largest city, located in the northern part of the state. Home to Anderson Japanese Gardens and a growing aerospace manufacturing sector.
Peoria
A central Illinois city on the Illinois River, long used as a test market for consumer products — giving rise to the phrase 'Will it play in Peoria?'
Galena
A beautifully preserved 19th-century lead mining town in the northwest corner. Ulysses S. Grant's pre-Civil War home is a museum here.
Capital city data: Census Bureau ACS 5-Year (2022)
Intel File · Fun Facts
Chicago's elevated rail system, the 'L,' has been running since 1892 and is one of the oldest rapid transit systems in the world.
Illinois is the only state where a current or former governor has been convicted of a crime — four governors have been imprisoned.
The first McDonald's franchise was opened by Ray Kroc in Des Plaines, Illinois in 1955.
Route 66, 'The Mother Road,' begins at the Art Institute of Chicago on Adams Street.
Illinois produces more pumpkins than any other state — over 90% of processing pumpkins used for canned pumpkin pie filling come from Illinois.
Data & Statistics
Demographics
- Population
- 12,757,634
- Median income
- $78,433
- Median age
- 38.7
- Median home value
- $239,100
- Below poverty line
- 1,467,893
- Bachelor's degree+
- 1,924,339
Source: U.S. Census Bureau, ACS 5-Year Estimates (2022)
Agriculture
- Total farms
- 71,123
- Cropland
- 22,913,841 acres
- Market value
- $26,417M
Source: USDA NASS, Census of Agriculture (2022)
Public Health
- Obesity rate
- 36.0%
- Diabetes rate
- 12.2%
- Smoking rate
- 10.8%
- High blood pressure
- 33.5%
- Uninsured
- 6.6%
Source: CDC BRFSS Prevalence Data (2023, 2022 fallback)
National Parks & Sites
- National parks
- 0
- Total NPS sites
- 8
- Sites
- Emmett Till and Mamie Till-Mobley National Monument, Lewis & Clark National Historic Trail, Lincoln Home National Historic Site, Mormon Pioneer National Historic Trail, New Philadelphia National Historic Site, Pullman National Historical Park, Springfield 1908 Race Riot National Monument, Trail Of Tears National Historic Trail
Source: National Park Service API
Climate
- Avg temperature
- 52.0°F
- Avg high
- 62.2°F
- Avg low
- 41.7°F
- Annual precipitation
- 39.3 in
- Annual snowfall
- 18.0 in
Source: NOAA Climate Normals (2010)
Frequently Asked Questions
What is the capital of Illinois?▾
Springfield is the capital of Illinois — not Chicago, as many people assume. Springfield has been the state capital since 1837 and is best known as the home of Abraham Lincoln.
Why is Chicago called the Windy City?▾
The nickname 'Windy City' likely originated in the late 19th century. While Chicago is windy (averaging 10.3 mph), the nickname may also reference the city's boastful politicians — rival cities mocked Chicago's 'windy' rhetoric during its bid for the 1893 World's Fair.
What is Illinois known for?▾
Illinois is known for Chicago (deep-dish pizza, architecture, blues music), Abraham Lincoln's legacy in Springfield, vast corn and soybean farms, Route 66, and being a major transportation and financial hub.
What is the Garden of the Gods in Illinois?▾
The Garden of the Gods is a stunning rock formation in the Shawnee National Forest in southern Illinois. The sandstone formations were shaped over 300 million years and offer panoramic views of the surrounding forest. It is one of the most photographed spots in the state.
Data sources
U.S. Census Bureau · USDA NASS · CDC BRFSS · National Park Service · NOAA CDO
This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau. This product uses the NASS API but is not endorsed or certified by NASS.
© 2026 GeoProwl. All rights reserved.