On both sides of the state, the respective river crossings opened to traffic nearly two years later than the connecting highways. Near LeClaire, the Fred Schwengel Memorial Bridge over the Mississippi River opened in 1966 after the highway had been completed to US 67, which runs at the foot of the bridge, in 1964. The center span of the Mississippi River bridge was installed on June 29, 1966. The , piece was floated into place by barge. In Council Bluffs, the Missouri River crossing opened on December 15, 1972, while the approach to the bridge opened in November 1970. The Missouri River bridge's completion marked the end of the 14 years it took to construct Interstate 80.