The Calumet Region is the name given to the geographic areas drained by the Grand Calumet River and the Little Calumet River of northeastern Illinois and northwestern Indiana in the United States. It is part of the Great Lakes Basin, which eventually reaches the Atlantic Ocean. This region includes the northern parts of Lake and Porter counties and the western portion of La Porte county in Indiana, as well as the eastern counties of northern Illinois, Will and Cook. Since much of this region is on the south shore of Lake Michigan, it is sometimes referred to as the "South Shore". Because it was initially cut off from the rest of the state due to natural geographic barriers like the Kankakee Marsh to the south, the Calumet Region was the last-settled portion of Indiana. It is a sub-region o