Gary is a city in Lake County, Indiana, United States. As of the 2020 census the city's population was 69,093, making it Indiana's ninth-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.

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.