While the Duke is known for his interest in science and engineering, the Queen was also said by fellow passengers to have been deeply knowledgeable about the railways, saying she loved them for making travel so easy.

Isambard Thomas, the great-great-great-grandson of Isambard Kingdom Brunel who sat next to her en route to London, said: "It was fascinating how much interest she has in trains and in train journeys.”

He joked: "Obviously it's a different thing if you're the monarch; you're not sat in second class, queuing for the buffet."