U.S. Highway 6 (US 6) is an east–west U.S. Highway which runs 319 miles (513 km) across the U.S. state of Iowa. The route is signed in places as the Grand Army of the Republic Highway. Like all state highways in Iowa, it is maintained by the Iowa Department of Transportation. The route begins at the Missouri River crossing at Council Bluffs. From there, it travels east through Oakland and Atlantic. North of Atlantic, the highway overlaps Interstate 80 (I-80) until De Soto. Between De Soto and Adel, the highway overlaps US 169 before splitting off to the east towards Des Moines. Through the Des Moines area, the highway runs about one mile (1.6 km) north or south of the I-35 / I-80 corridor.