The St. Lawrence Seaway was officially opened by U.S President Dwight Eisenhower and Her Majesty Queen Elizabeth II on June 26, 1959. A ceremonial sailing took the Royal Yacht Britannia through the seven locks of the Montreal to Lake Ontario section of the seaway, raising the vessel to more than 245 feet above sea level, calling at five Canadian cities and two American ports. Today, it is considered one of the most important trade routes in the world.
