Eureka, Illinois

Eureka, Illinois
Interactive map of Eureka, Illinois
Eureka
Eureka
Coordinates: 40°42′54″N 89°16′39″W / 40.71500°N 89.27750°W / 40.71500; -89.27750
CountryUnited States
StateIllinois
CountyWoodford
Founded1855
Government
 • MayorEric Lind
Area
 • Total
2.73 sq mi (7.08 km2)
 • Land2.68 sq mi (6.95 km2)
 • Water0.046 sq mi (0.12 km2)
Elevation
738 ft (225 m)
Population
 (2020)
 • Total
5,227
 • Estimate 
(2024)
5,189
 • Density1,947.3/sq mi (751.86/km2)
Time zoneUTC-6 (CST)
 • Summer (DST)UTC-5 (CDT)
ZIP code
61530
Area code309
FIPS code17-24543
GNIS ID2394706
Websitewww.eurekaillinois.net

Eureka is a city in and the county seat of Woodford County, Illinois, United States. As of the 2020 census, Eureka had a population of 5,227. Eureka is part of the Peoria metropolitan area.

Eureka is a small community centered on the intersection of what is now U.S. 24 and Illinois 117. It is also one of the towns along the Ronald Reagan Trail, a series of roads that connect towns in central Illinois that were of importance to Reagan's early life. President Reagan attended and graduated from Eureka College.