Indiana is a U.S. state located in the midwestern and Great Lakes regions of North America. Indiana is the 38th largest by area and the 16th most populous of the 50 United States. Indiana is the least extensive state in the contiguous United States west of the Appalachian Mountains. Its capital and largest city is Indianapolis. Indiana was admitted to the United States as the 19th U.S. state on December 11, 1816.
Before it became a territory, varying cultures of indigenous peoples and historic Native Americans inhabited Indiana for thousands of years. Since its founding as a territory, settlement patterns in Indiana have reflected regional cultural segmentation present in the Eastern United States; the state's northernmost tier was settled primarily by people from New England and New York, Central Indiana by migrants from the Mid-Atlantic states and from adjacent Ohio, and Southern Indiana by settlers from the Southern states, particularly Kentucky and Tennessee.
With a total area (land and water) of 36,418 square miles (94,320 km2), Indiana ranks as the 38th largest state in size. The state has a maximum dimension north to south of 250 miles (400 km) and a maximum east to west dimension of 145 miles (233 km). The state’s geographic center (39° 53.7’N, 86° 16.0W) is in Marion County.
Located in the midwestern United States, Indiana is one of eight states that make up the Great Lakes Region. Indiana is bordered on the north by Michigan, on the east by Ohio, and on the west by Illinois, while Lake Michigan borders Indiana on the northwest and the Ohio River separates Indiana from Kentucky on the south.
The average altitude of Indiana is about 760 feet (230 m) above sea level. The highest point in the state is Hoosier Hill in Wayne County at 1,257 feet (383 m) above sea level. The lowest point at 320 feet (98 m) above sea level is located in Posey County, where the Wabash River flows into the Ohio River. Only 2,850 square miles (7,400 km2) have an altitude greater than 1,000 feet (300 m) and this area is enclosed within 14 counties. About 4,700 square miles (12,000 km2) have an elevation of less than 500 feet (150 m).
The state includes two natural regions of the United States, the Central Lowlands and the Interior Low Plateaus. The till plains make up the northern and central allotment of Indiana. Much of its appearance is a result of elements left behind by glaciers. Central Indiana is mainly flat with some low rolling hills (except where rivers cut deep valleys through the plain, like at the Wabash River and Sugar Creek) and soil composed of glacial sands, gravel and clay, which results in exceptional farmland. Northern Indiana is also very similar except for the presence of higher and hillier terminal moraines and many kettle lakes in some regions. In northwest Indiana, there are various sand ridges and dunes, some reaching near 200 feet in height. These are located along the Lake Michigan shoreline and also inland to the Kankakee River Valley. The unglaciated southern segment of the state carries a different and off-balance surface, characterized in places by profound valleys and rugged, hilly terrain much different from the rest of the state.Here, bedrock is exposed at the surface and isn't buried in glacial till like further north. There are numerous caves in the area. The soil is fertile in the valleys of southern Indiana.
Major river systems in Indiana include the Whitewater, White, Blue, Wabash, St. Joseph, and Maumee rivers. According to the Indiana Department of National Resources, in 2007 there were 65 rivers, streams, and creeks of environmental interest or scenic beauty, which included only a portion of an estimated 24,000 total river miles within the state. The Wabash River, which is the longest free-flowing river east of the Mississippi River, is the official river of Indiana.
At 475 miles (764 km) in length, the river bisects the state from northeast to southwest before flowing south, mostly along the Indiana-Illinois border. The river has been the subject of several songs, such as On the Banks of the Wabash, The Wabash Cannonball and Back Home Again, In Indiana. The Kankakee River passes through northern Indiana before emptying into the Illinois River and serves as a demarcating line between suburban northwest Indiana and the rest of the state.
There are over 1,000 lakes in Indiana. To the northwest, Indiana borders Lake Michigan, where the Port of Indiana operates the state's largest shipping port. Tippecanoe Lake, the deepest lake in the state, reaches depths at nearly 120 feet (37 m), while Lake Wawasee is the largest natural lake in Indiana.