Indiana Geography: Lake Michigan Dunes, Glacial Plains, and Hill Country

Indiana spans three physiographic provinces — the glaciated till plain of the north and center, the unglaciated hills of the south, and the Lake Michigan shoreline of the northwest.

Lake Michigan Shore (Northwest Indiana)
Indiana has only 45 miles of Lake Michigan shoreline — but Indiana Dunes National Park preserves 15 miles of this shoreline with dunes reaching 123 feet. The Calumet Industrial District (Gary, Hammond, East Chicago) occupies the southern Lake Michigan shore with the largest steel complex in the US; the dunes park preserves the natural landscape adjacent to the industrial zone. Lake Michigan's southeast corner is warmer and clearer than the northern lake; the beach and swimming conditions are excellent in summer.

Central Indiana Till Plain
The broad, flat agricultural heartland — from the Lake Erie watershed in the northeast to the Ohio River watershed in the southeast. The Tipton Till Plain (the flattest part of Indiana, in Tipton, Hamilton, and Clinton Counties) has among the richest agricultural soils in the US. Indianapolis sits on the White River in the center of this plain.

Southern Indiana Hill Country
South of the terminal moraine (the southernmost extent of glaciation) — the unglaciated Hoosier Hills have rolling terrain, forested hollows, and the spectacular sandstone landscape of the Hoosier National Forest. Brown County State Park (the largest state park in Indiana, centered on a sandstone upland) is the most visited natural area in the state. The Ohio River valley has the state's most dramatic river scenery.

Kankakee River and Northern Wetlands
Northwestern Indiana — the Kankakee River valley was one of the largest wetland systems in the Midwest before drainage. The Grand Kankakee Marsh (once 500,000 acres) is now mostly farmland, but the Kankakee Fish & Wildlife Area preserves remnant marshes. The Indiana Dunes area has significant wetland buffers behind the dunes.

Wabash River
Indiana's longest internal river — the Wabash runs from the Ohio border to the Illinois border, forming the western boundary. The Wabash is the state river of Indiana (the song "On the Banks of the Wabash, Far Away" is the state song).