Monroe County
Sign in to savecounty in Illinois, United States
Key facts
- Country
- United States
- State
- Illinois
- Named after
- James Monroe
- Seat
- Waterloo
- Largest city
- Waterloo
- Total
- 398 sq mi (1,030 km )
- Land
- 385 sq mi (1,000 km )
- Water
- 13 sq mi (34 km ) 3.3%
- Estimate 2025
- 34,840
- Density
- 90.8/sq mi (35.1/km )
- Time zone
- UTC−6 ( Central )
- Summer dst
- UTC−5 ( CDT )
- Congressional district
- 12th
- Website
- monroecountyil .gov
via Wikipedia infobox
Article
Monroe County is a county located in the U.S. state of Illinois. According to the 2020 census, it had a population of 34,962. Its county seat and largest city is Waterloo. Monroe County is included in the St. Louis, MO-IL Metropolitan Statistical Area. It is located in the southern portion of Illinois known historically as "Little Egypt".
History