1959: Opening of the St. Lawrence Seaway

Construction of the 189-mile (306-kilometer) stretch of the Seaway between Montreal and Lake Ontario is recognized as one of the most challenging engineering feats in history. Seven locks were built in the MontrealLake Ontario section of the Seaway, five Canadian and two U.S., in order to lift vessels to 246 feet (75 meters) above sea level.

To this day, every year more than 160 million metric tons of cargo is moved on the Great Lakes-St. Lawrence Seaway System.