High Quality Content by WIKIPEDIA articles! Interstate 235 (I-235) in Iowa is an auxiliary Interstate Highway that runs just north of downtown Des Moines through the heart of the Des Moines metropolitan area. I-235 runs from the junction of Interstate 35 and Interstate 80 in West Des Moines to the separation of the same two interstates in Ankeny. The highway is approximately 14 miles (23 km) long.