Hammond is a city in Lake County, Indiana, United States. Located along Lake Michigan, it is part of the Chicago metropolitan area and the only city in Indiana to border Chicago. It was first settled in the mid-19th century and it is one of the oldest cities of northern Lake County. As of the 2020 census, it is also the county's largest city by population, with 77,879 residents.

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.