On This Day: Queen opens St Lawrence Seaway that connects Great Lakes to Atlantic in Canada

JUNE 26, 1959: The Queen opened the 2,300-mile St Lawrence Seaway that connects the American side of the Great Lakes to the Atlantic Ocean in eastern Canada on this day in 1959.

The monarch, who is the head of state in Canada as well as Britain, marked the occasion by sailing down the water highway in the Royal Yacht Britannia.

She was joined by U.S. President Dwight Eisenhower, whose nation contributed a third of the $470million cost of the project in a bid to boost international trade.

A British Pathé newsreel filmed Her Majesty and Prince Philip greeting the former top general and his wife Mamie as they jetted into Montreal, Quebec.

They were then driven together to the banks of the St Lawrence River, which was fully connected with Lake Superior via the construction of 370 miles of canals.

There, they each gave speeches, with Eisenhower making a few remarks in his ‘Western Prairie brand’ of French, the main language in Quebec.

The two heads of state then set sail on Britannia, where Canadian Prime Minister John Diefenbaker joined them.

It was a fitting way to open the new gateway to the North American heartland.

The Great Lakes – the world’s largest body of fresh water, which encompass Lakes Superior, Michigan, Huron, Ontario and Erie – were already all inked by rivers.

But the St Lawrence Seaway’s new canals bypassed the virtually un-navigable rapids on the St Lawrence and Niagara Rivers, including the raging Niagara Falls.

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It connected Montreal, with its unfettered access to the Atlantic, with the U.S. city of Duluth, Minnesota some 1,000 miles west if travelling in a straight line.

It also gave the major American cities of Chicago and Detroit access to the ocean and enabled newly reachable Toronto to become Canada’s economic powerhouse.

Altogether, some 100million people in two of the richest countries on earth live near the St Lawrence Seaway, making it a highly lucrative trade channel.

Today, it handles 50million tons of cargo - mainly grain, iron ore, coal and steel – with some 6,500 ships passing per year.

Plans for a canal system were first made in the 1700s, but it was not until 1954 – after a joint agreement between the U.S. and Canada – that construction began.

It required the building of 14 locks, existing waterways to be dredged and a 100 square mile area to be flooded, which meant 6,500 people needed to be resettled.

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After opening the canal, the Queen sailed on Britannia all the way to Chicago in the first Royal visit to the U.S. city.

The vessel, which was launched in 1953, carried out 968 official voyages all over the globe and steamed 1,087,623 nautical miles before being decommissioned in 1997.

Among other illustrious voyages, Charles and Diana, the new Prince and Princess of Wales, took their honeymoon cruise aboard HMY Britannia in 1981.

The ship, which carried a platoon of Marines when members of the Royal Family were aboard, also evacuated over 1,000 refugees from the civil war in Aden in 1986.

There were even secret plans for the Queen to use the Royal Yacht in the event of nuclear war.

Britannia set sail on her final voyage from Hong Kong following the official handover to China on July 1, 1997.

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Chris Patten, the last governor of the former British territory, was joined by Prince Charles on the vessel as it returned to Portsmouth.

In April 1998, the city of Edinburgh won a nationwide competition to be Britannia's new home and she is now permanently moored at the port of Leith.

The vessel, which is owned by The Royal Yacht Britannia Trust, is now visited by 250,000 people a year and a major tourist attraction.