Lake County is a county located in the U.S. state of Indiana. In 2020, its population was 498,700, making it Indiana's second-most populous county. The county seat is Crown Point. The county is part of Northwest Indiana and the Chicago metropolitan area, and contains a mix of urban, suburban and rural areas. It is bordered on the north by Lake Michigan and contains a portion of the Indiana Dunes. It includes Marktown, Clayton Mark's planned worker community in East Chicago.

The Kankakee River is a tributary of the Illinois River, approximately 133 miles (214 km) long, in the Central Corn Belt Plains of northwestern Indiana and northeastern Illinois in the United States. At one time, the river drained one of the largest wetlands in North America and furnished a significant portage between the Great Lakes and the Mississippi River. Significantly altered from its original channel, it flows through a primarily rural farming region of reclaimed cropland, south of Lake Michigan.