For all the grand Royal palaces at his disposal, it is a rather more modest address which Prince Philip chooses to call home.
Wood Farm, an unassuming cottage on the edge of the Sandringham Estate close to the Norfolk coastline, is where the Duke has been whiling away his days since retiring from official public life in August 2017.
The red-brick, five-bedroom property with its spartan furnishings and cosy open fires has for years been a bolthole from stuffy palace formality.
Royal observers note that the Queen and Philip have been able to feel – and, indeed, behave – like normal people while staying at Wood Farm rather than in ‘the big house’ a few miles away across the estate.
Pictured: Prince Philip, the Duke of Edinburgh, with Lady Penny Brabourne at the Royal Windsor Horse Show
While the Queen continues to carry out official duties around the country, Prince Philip spends his days in Norfolk reading history books and biographies – he is said to regard novels with ‘suspicion’ – painting watercolours and entertaining friends and family who arrive by train from London.
His most recent visitors were Prince Charles, Prince Edward and Edward’s son, 12-year-old James. The Queen stays occasionally, although they are said to speak on the phone every day. Philip’s most regular visitor is one who also shares his greatest and most perilous passion – carriage riding.
Penny Brabourne, 66, the estranged wife of Earl Mountbatten, is a long-time friend and confidante of the Duke.
The pair also share an appreciation for the Mountbatten family’s Broadlands home, which Penny is running due to her husband’s ill-health.
Carriage riding involves sitting on a vehicle being pulled by horses and, while it may sound sedate, it is done at speed and requires considerable nerve and skill.
Royal biographer Hugo Vickers said: ‘Prince Philip and Penny have been doing this together for years as a mutual interest.
‘He absolutely loves it and will do it every day, including Sundays. He took it up when he was forced to give up polo in 1971 due to an arthritic wrist.
Wood Farm (pictured), an unassuming cottage on the edge of the Sandringham Estate close to the Norfolk coastline, is where the Duke has been whiling away his days since retiring
‘He terrified his guests. Once, he took someone on his carriage and told him, ‘Horses get used to the way they normally go and usually they’d turn right here. I’m going to make them turn left – and they won’t like it.’
‘He was right. The guest was thrown from the carriage, while Prince Philip was thrown the other way. After they were rescued and safely in the back of a Land Rover, the Duke simply turned to him and quipped, ‘See what I mean?’
‘I’ve seen him do it and it looks terrifying but his former private secretary says it’s relaxation for him.
‘If you’re doing it at speed and going around obstacles, you have to concentrate so hard you don’t have time to think about anything else. That’s the point of it for him, I think.’
Penny and the Duke ‘get on very well together’, he added.
‘I’ve seen them all together – the Queen, Prince Philip and Penny – at Windsor and she stays at the castle. They spend a lot of time in each other’s company.’
Wood Farm was once the home of the so-called Lost Prince – Prince John, the youngest son of George V and Queen Mary.
His tragic story was turned into an Emmy award-winning 2003 BBC drama.
The Prince, who had epilepsy and learning difficulties, was sent to live in the cottage with his nanny to shield him from the public gaze, but he regularly saw his grandmother, Queen Alexandra, who was living at Sandringham. He died in 1919 aged just 13.
Wood Farm had been occupied by a tenant until it was turned back into a Royal residence.
Mr Vickers added: ‘Wood Farm is more practical than opening up Sandringham. It’s not tiny, but it’s a normal house that anyone could live in. It’s very un-Royal.’
Just, perhaps, the way the Duke likes it.