The royal couple paid an unofficial visit to Greece to stay with Philip’s cousin King Paul. They stayed in the royal palace in Athens where the Parthenon was floodlit in their honour. According to cousin Alexandra, when Philip took King Paul aboard Magpie he was astonished to find that Philip’s quarters were full of papers on which Philip was working, including preparations for the Festival of Britain and the overseas tour of Canada. Philip had an interest in the festival as a showpiece for the inventiveness of British scientists and for British technology. It was planned for the centenary of the Great Exhibition, in which Prince Albert had played such an important role.

Although frail, George VI opened the festival on 3 May 1951, but he was soon struck down with a bug he could not shake off. His doctors ordered complete rest and cancellation of all public engagements; Elizabeth and Philip would have to take over. In July, Philip left Malta ‘on indefinite leave’. As the crew of Magpie lined the decks to cheer him off, he said: ‘I have kept my promise to make HMS Magpie one of the finest ships in the fleet. The past eleven months have been the happiest of my sailor life.’ Back at Clarence House, he looked sadly at his white naval uniforms and said to John Dean: ‘It will be a long time before I want those again.’

During the summer, Elizabeth stood in for her father at many public engagements, including Trooping the Colour. Detailed plans had been made for Elizabeth and Philip to pay an official state visit to Canada in September, but the King had been advised by his doctors that he should have an operation to remove his left lung, which was duly performed. Rather than set sail for Canada in the days after the operation, Philip persuaded the government that he and the princess should travel by air to avoid delaying the start of the tour.

When they landed, a nervous 25-year-old Princess Elizabeth stepped out onto the airplane gangway in Montreal on 8 October 1951, a crowd of 15,000 before her on the tarmac. She was about to begin her first major royal visit, during which she would be the centre of attention. The tour lasted thirty-three days during which time the royal couple travelled from coast to coast and back again. The tour was a great success, with hugely enthusiastic crowds at every stop.