Tremont, Indiana, is a ghost town formerly located in what is now the Indiana Dunes State Park and Indiana Dunes National Park in Westchester Township in northern Porter County, Indiana. It was first established in 1833. It was located at the intersection of U.S. Highway 12 and County Road 100 East, near Indiana 49. The community is named for three massive sand dunes that are now contained within the State park. They are Mount Tom, Mount Holden 170 feet (52 m), and Mount Green 160 feet (49 m).

Indiana Dunes National Park is a United States national park located in northwestern Indiana managed by the National Park Service. It was authorized by Congress in 1966 as the Indiana Dunes National Lakeshore and was redesignated as the nation's 61st national park on February 15, 2019. The park runs for about 20 miles (32 km) along the southern shore of Lake Michigan and covers 15,349 acres (6,212 ha). Along the lakefront, the eastern area is roughly the lake shore south to U.S. 12 or U.S. 20 between Michigan City, Indiana, on the east and the Cleveland-Cliffs steel plant on the west. This area's conservation scheme is enhanced by the older Indiana Dunes State Park. To the west of the steel plant lies West Beach and a small extension south of the steel mill continues west along Salt Creek to Indiana 249. The western area is roughly the shoreline south to U.S. 12 between the Burns Ditch west to Broadway in downtown Gary, Indiana. In addition, there are several outlying areas, including Pinhook Bog, in LaPorte County to the east; the Heron Rookery in Porter County, the center of the park; and the Hoosier Prairie State Nature Preserve and the Hobart Prairie Grove, both in Lake County, the western end of the park.