The realisation came after the Duke had spent a rather long journey on a train in 1952.
Prior to the Queen’s ascension to the throne, the then-princess and Philip jetted off to Canada on a royal tour.
The problem for the Duke was the fact most of the travelling across the vast nation was down by train.
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“If it was snug and well insulated against the increasingly bracing weather, the Duke found it faintly claustrophobic,” continued Hardman.
“‘I feel like a poached egg. I just can’t breathe on trains,’ he announced as he disembarked in Vancouver.”
Despite his aversion to trains, however, the prince has still taken part in a number of journeys.
Unsurprisingly, the royal train is also kitted out to meet specific requirements in order to make the Prince feel as comfortable as possible.
This opulence even extends to the Duke’s specially designed bathroom.
In order to enjoy some of his home comforts, the Prince requested some special “design details” to be put in place within his bathroom.
“His royal highness Prince Philip has a shaving mirror mounting next to his toilet,” explained Chris Hillyard, a former royal train foreman.
“So you can sit on the toilet and look in the mirror and shave.
“That was one of the little design details that weren’t incorporated in the original built.”