Chouteau Island ( /ʃuːˈtoʊ/ shoo-toh), situated approximately 8 miles (13 km) due north of the St. Louis, Missouri Gateway Arch and approximately 1-mile (2 km) south of the confluence of the Missouri River and Mississippi River, is one of a cluster of three islands: Chouteau, Gabaret, and Mosenthein. The three, with a combined area of approximately 5,500 acres (20 km2), are located in Madison County, Illinois. The Island is manmade, having been created during the US construction of the Chain of Rocks Canal between 1946 and 1953.
Chouteau Island is bounded by the Mississippi River to the west and the Chain of Rocks Canal to the east. The 10 miles (20 km) of Mississippi River that border the Island on the west is the only natural stretch of the Mississippi without barge traffic between St. Paul, Minnesota and New Orleans, Louisiana.
Chouteau Island is accessed by car only from Illinois via the Canal Bridge, a 2-lane vehicular bridge that crosses the Chain of Rocks Canal. From Missouri, visitors may reach the Island by foot/bicycle traffic via U.S. Route 66's Old Chain of Rocks Bridge, but it is no longer open to motor vehicle traffic.
Chouteau Island is a key part of the Confluence Greenway, a regional recreation corridor. Popular events on the Island, include Eagle Days (held each January for watching bald eagles) and various recreational bicycle rides. Several walking/biking trails have been developed on the Island.
Lewis and Clark camped on Gabaret Island on December 11, 1803, prior to establishing Camp Dubois near Wood River, Illinois.
Mississippi River Lock #27 (Chain of Rocks Lock) is located at the south end of the Island.
Following the Great Flood of 1993, governments acquired all residences within the Island complex. Over 70% of Chouteau Island is now in public ownership, under the U.S. Army Corps of Engineers, the Illinois Department of Natural Resources and the city of Madison, Illinois. They are collaborating to develop Chouteau Island as a recreational complex to feature floodplain and grasslands restoration, additional trails, interpretive overlooks, picnic areas, camping areas and a visitors center near the entrance to the Old Chain of Rocks Bridge.