Iowa Highway 175 (Iowa 175) is a main east–west route in the northern portion of the state. The highway has a length of 221 miles (356 km). Iowa Highway 175 enters the state by a Missouri River crossing between Decatur, Nebraska and Onawa. The highway continues westward as Nebraska Highway 51. Iowa 175's eastern terminus is at a T intersection with U.S. Highway 63 (US 63) in southwestern Black Hawk County.

Iowa Highway 17 is a 103-mile-long (166 km) north–south state highway that traverses primarily rural areas in central and north-central Iowa. Iowa 17's southern end is near Granger in Dallas County at a freeway interchange with Iowa Highway 141, and its northern terminus is at an intersection with U.S. Highway 18 at the Kossuth-Hancock county line near Wesley.