Royalton, Indiana  Royalton is an unincorporated community in Eagle Township, Boone County, in the U.S. state of Indiana. A post office was established at Royalton (but was called Rodmans until 1838) in 1832, and remained in operation until it was discontinued in 1903. Royalton is located at . Royalton is located along Indianapolis Rd approximately 0.7 miles northwest of Marion County. The town is made up of three main streets - Royal Avenue, Circle Drive, and Harmon Avenue.