1991 Map of Illinois City

About this map

The Mississippi River forms a complex hydrologic network as it crosses the border between Iowa and Illinois, characterized by a series of significant islands and secondary channels. Along the northern bank in Iowa, the landscape is defined by the steep wooded ravines of Wildcat Den State Park and the structured grounds of the Fairport State Fish Hatchery. The river itself is divided by Geneva Island, Hog Island, and Hershey Island, which create the slow-moving waters of Wyoming Slough and Hershey Slough.