Located in the Midwestern United States and bordered by Nebraska, Missouri, Oklahoma and Colorado, Kansas was named after the Kansa Native American tribe which inhabited the area. Its capital city is Topeka, and its largest city is Wichita, known as "The Air Capital of the World". The western two-thirds of the state, lying in the great central plain of the United States, has a generally flat surface, while the eastern third has many hills and forests.