The Old Man of Lochnagar is a children's story written by Prince Charles (now King Charles III of the UK). The story follows a whimsical old man who lives in a cave near the Scottish mountain of Lochnagar and embarks on various adventures, meeting unusual characters and exploring the local environment. The tale is known for its gentle humour and appreciation of nature. Originally created by the Prince for his younger brothers, the book is a charming piece of children's literature, promoting imagination and a love for the natural landscape of Scotland.