Monroe County

Monroe County occupies southwestern Illinois and features a landscape of limestone bluffs, caves, and natural springs. The terrain stretches across the Mississippi River floodplain with numerous sinkholes dotting the ground.

The county was established in 1816 and named after James Monroe, the fifth president. It grew from earlier French settlements that had been built in the early 1700s.

The area reflects German and Irish roots through local customs and celebrations held across its towns. These influences shape how people here mark important occasions and gather as communities.

The county seat of Waterloo serves as the main hub for services and is connected by Interstate 255 and Highway 50. These routes provide direct access to the St. Louis area for residents and visitors.

The area contains roughly 500 limestone sinkholes that create a distinctive karst landscape uncommon in Illinois. This geological pattern shapes the ground beneath visitors' feet in unexpected ways.

Location: Illinois

Inception: January 6, 1816

Capital city: Waterloo

Shares border with: St. Clair County, Ste. Genevieve County, Randolph County, Jefferson County, St. Louis County

Website: http://monroecountyil.org

GPS coordinates: 38.28000,-90.18000

Latest update: December 7, 2025 19:24