Map of Hamilton County, Illinois

Hamilton County is a county located in the U.S. state of Illinois. At the 2020 census, its population was 7,993. Its county seat is McLeansboro. It is located in the southern portion of the state known locally as “Little Egypt”.

Hamilton County overview:
Name:	Hamilton County
FIPS code:	17-065
State:	Illinois
Founded:	1821
Named for:	Alexander Hamilton
Seat:	McLeansboro
Largest city:	McLeansboro
Total Area:	436 sq mi (1,130 km²)
Land Area:	435 sq mi (1,130 km²)
Total Population:	7,993
Population Density:	18/sq mi (7.1/km²)
Time zone:	UTC−6 (Central)
Summer Time Zone (DST):	UTC−5 (CDT)
Website:	www.hamiltoncountyillinois.com

Hamilton County location map. Where is Hamilton County?

Hamilton County location on the U.S. Map. Where is Hamilton County. — Location of Hamilton County in the the United States.

Hamilton County location on the Illinois map. Where is Hamilton County. — Location of Hamilton County in Illinois.

History

Hamilton County was formed out of White County in 1821. It is named for Alexander Hamilton, Revolutionary War hero and the first United States Secretary of the Treasury.

Hamilton County at the time of its creation in 1821

On March 18, 1925, the infamous Tri-State Tornado tore across the county, destroying dozens of homes and farms in Flannigan, Twigg, Mayberry and Crook townships, and killing 37 people.

Hamilton County Road Map

Hamilton CountyStreet Map. — Street map of Hamilton County, Illinois. Source: OpenStreetMap (OSM)

Hamilton CountyMap — Hamilton Countypolitical map.

Geography

According to the U.S. Census Bureau, the county has a total area of 436 square miles (1,130 km), of which 435 square miles (1,130 km) is land and 1.2 square miles (3.1 km) (0.3%) is water.

Climate and weather

In recent years, average temperatures in the county seat of McLeansboro have ranged from a low of 20 °F (−7 °C) in January to a high of 89 °F (32 °C) in July, although a record low of −23 °F (−31 °C) was recorded in January 1930 and a record high of 113 °F (45 °C) was recorded in July 1936. Average monthly precipitation ranged from 2.76 inches (70 mm) in February to 4.67 inches (119 mm) in May.