Geography of Alexander County, Illinois

By | March 13, 2024

Alexander County, located in the southernmost part of Illinois, is characterized by its unique geography, rich history, and diverse ecosystems. From its position along the Mississippi River to its rolling hills and fertile farmland, Alexander County offers a blend of natural beauty and cultural heritage. See topschoolsintheusa for information about Champaign, Illinois.


Alexander County covers an area of approximately 244 square miles, making it one of the smaller counties in Illinois by land area. It is situated in the southern tip of the state, bordered by the Mississippi River to the west and the Ohio River to the south, with Pulaski County to the east and Union County to the north. The county seat is Cairo, while other communities include Tamms and McClure.


Alexander County experiences a humid subtropical climate, characterized by hot, humid summers and mild winters. Average high temperatures in the summer months typically range from the upper 80s to low 90s Fahrenheit, while winter highs average in the 40s and 50s.

Precipitation is evenly distributed throughout the year, with moderate rainfall in the spring and fall months and occasional snowfall in the winter. The region’s climate is influenced by its proximity to the Mississippi and Ohio Rivers, which can bring heavy rainfall and flooding during the spring and summer months.


The Mississippi River forms the western border of Alexander County, separating it from the state of Missouri. One of the longest rivers in North America, the Mississippi River serves as a vital transportation corridor for the region, supporting shipping, commerce, and industry.

In addition to the Mississippi River, Alexander County is intersected by the Ohio River, which forms the southern border of the county. The confluence of these two major rivers near the city of Cairo has historically been an important strategic and economic hub, shaping the county’s history and development.

Natural Areas:

Alexander County is home to several natural areas and wildlife refuges, which provide habitat for a variety of plant and animal species. The Cypress Creek National Wildlife Refuge, located in the southern part of the county, encompasses over 16,000 acres of wetlands, forests, and open water, providing sanctuary for migratory birds, waterfowl, and other wildlife.

The Cache River State Natural Area, located near the town of Tamms, features pristine wetlands, bottomland hardwood forests, and cypress swamps, as well as hiking trails and wildlife viewing opportunities. These natural areas offer visitors a chance to explore the unique ecosystems of southern Illinois and observe rare and endangered species in their native habitats.

Farming and Agriculture:

Despite its proximity to the rivers, much of Alexander County is characterized by fertile farmland and agricultural fields. The county’s agricultural economy is based primarily on corn, soybeans, wheat, and other row crops, as well as livestock such as cattle and poultry.

Farmers markets and roadside stands offer locally grown produce and agricultural products, including fresh fruits and vegetables, honey, and homemade crafts. Agritourism attractions, such as pumpkin patches and corn mazes, provide opportunities for visitors to experience farm life and support the local economy.

Historical and Cultural Heritage:

Alexander County has a rich history dating back to its early settlement by Native American tribes, followed by European explorers and settlers in the 18th and 19th centuries. The city of Cairo, founded in the early 19th century at the confluence of the Mississippi and Ohio Rivers, played a significant role in the region’s history as a transportation and trade center.

The county is also home to several historic sites and landmarks, including the Cairo Custom House and Post Office, a National Historic Landmark built in the late 19th century. Other notable sites include Fort Defiance Park, located at the confluence of the Mississippi and Ohio Rivers, and the Old Civil War Fortifications, which date back to the Civil War era.

Outdoor Recreation:

Alexander County offers a variety of outdoor recreational opportunities for residents and visitors alike. In addition to boating, fishing, and wildlife viewing on the Mississippi and Ohio Rivers, outdoor enthusiasts can enjoy hiking, birdwatching, and camping in the county’s natural areas and wildlife refuges.

The county is also home to several parks and recreational facilities, including Alexander Park in Cairo, which features playgrounds, picnic areas, and sports fields. In addition, the Shawnee National Forest, located just to the east of the county, offers miles of hiking trails, scenic overlooks, and camping opportunities in a pristine natural setting.


In conclusion, Alexander County, Illinois, offers a unique blend of natural beauty, cultural heritage, and outdoor recreation opportunities. From its position along the Mississippi and Ohio Rivers to its rolling hills and fertile farmland, the county provides a diverse array of landscapes and ecosystems to explore and enjoy. Whether boating on the rivers, hiking in the forests, or learning about the area’s history at a local museum, there is something for everyone to discover in Alexander County.