Lake County, Indiana in the context of "Indiana Dunes"

Gary is a city in Lake County, Indiana, United States. The population was 69,093 at the 2020 census, making it Indiana's eleventh-most populous city. The city has been historically dominated by major industrial activity and is home to U.S. Steel's Gary Works, the largest steel mill complex in North America.

Gary is located along the southern shore of Lake Michigan about 25 miles (40 km) southeast of downtown Chicago. The city is the western gateway to the Indiana Dunes National Park, and is within the Chicago metropolitan area.

41°33′N 87°27′W / 41.55°N 87.45°W / 41.55; -87.45The Calumet Region is the geographic area 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. It is a sub-region of the greater Northwest Indiana region and the even larger Great Lakes region.

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.

Northwest Indiana, commonly referred to as "The Region" after the Calumet Region, is an unofficial geographic area in the northwestern corner of Indiana in the United States. Although its boundaries are not formally defined, the area is generally associated with the Gary, Indiana Metropolitan Division, which includes Jasper, Lake, Porter and Newton counties, and the Michigan City–La Porte Metropolitan Statistical Area, which includes LaPorte County, with some broader definitions also including Starke and Pulaski counties.

The area borders Lake Michigan and portions of it are considered part of the Chicago metropolitan area. Based on the 2020 United States census, the broadest definition of Northwest Indiana has a population of 866,965, making it the second-largest urban area in the state after the Indianapolis metropolitan area.

The Valparaiso Moraine is a recessional moraine (a landform left by receding glaciers) that forms an immense U around the southern Lake Michigan basin in North America. It is a band of hilly terrain composed of glacial till and sand. The Valparaiso Moraine defines part of the continental divide known as the Saint Lawrence River Divide, bounding the Great Lakes Basin. It begins near the border of Wisconsin and Illinois and extends south through Lake, McHenry, Cook, DuPage and Will counties in Illinois, and then turns southeast, going through northwestern Indiana. From this point, the moraine curves northeast through Lake, Porter, and LaPorte counties of Indiana into Michigan. It continues into Michigan as far as Montcalm County.

The moraine was formed during the Crown Point Phase of the Wisconsin glaciation. At this time the glacier covering the area had grown thin, so it was restrained by dolomite rock layers in the Lake Michigan basin. Where the glacier stopped, glacial till and sand was deposited, creating the hills of the moraine. After the Valparaiso Moraine was formed, the glacier retreated and formed the Tinley Moraine.

Hoosier Prairie is a unit of Indiana Dunes National Park in Lake County, Indiana. It began in the 1970s as wasteland that the Hoosier Prairie Committee founded by Irene Herlocker-Meyer found of unique interest. From a core of 304 acres (123 ha), it has grown to 1,547 acres (626 ha) of important prairie habitat. The area was designated a National Natural Landmark in 1974 and a State Nature Preserve in 1977 The sandy soil creates a variety of habitats, from oak barrens, wet prairie, including sedge meadows and prairie marshes. More than 350 native species of vascular plants have been identified. A minimum of 43 species are uncommon in the State of Indiana.