River Indiana is a term used to refer to two major rivers in the state of Indiana: the Wabash and the Maumee. The Wabash River is a 503-mile long river that flows through Indiana, Ohio, and Illinois. It is the largest river in Indiana and is a tributary of the Ohio River. The Maumee River is a 260-mile long river that flows through Indiana, Ohio, and Michigan. It is a tributary of Lake Erie and is the largest river in Ohio.