The exact moment when Princess Elizabeth became Queen Elizabeth is unknown. The reason is that her father, George VI, died in his sleep during the night of 5–6 February 1952 at the age of 56. However, we do know that, when she retired for the night, Elizabeth’s father was still alive; in the morning the 26-year old Elizabeth had formally acceded to the throne of the United Kingdom.

Elizabeth and her husband Philip were in Kenya at the time, as part of an official trip that was intended to take in Australia. The King, known to have been in poor health, had insisted on seeing them off on the 31 January. Part of the couple’s experience in Kenya was to stay at Treetops Hotel in Aberdare National Park near the township of Nyeri, 1,966 m (6,450 ft) above sea level, in sight of Mount Kenya. First opened in 1932 by Eric Sherbrooke Walker, Treetops Hotel was built into the tops of the trees of Aberdare National Park as a treehouse, offering the guests a close view of the local wildlife. The idea was to provide a machan (hunting platform on a tree during shikar in India) experience in relative safety and comfort.

The hunter Jim Corbett, who was invited by the princess to accompany them during their stay there, wrote in the visitors' log book: “For the first time in the history of the world, a young girl climbed into a tree one day a Princess and after having what she described as her most thrilling experience she climbed down from the tree next day a Queen – God bless her.”

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