From the Mirror archives June 26, 1959

Today’s picture shows the Queen and Duke of Edinburgh with US President Dwight D Eisenhower and his wife Mamie on board the royal yacht Britannia in Montreal, Canada. It marked the formal opening of the St Lawrence Seaway at Lambert Lock. The £269million system of locks and waterways enabled oceangoing vessels to travel from the Atlantic Ocean to the Great Lakes of North America via the St Lawrence River.