In my book Kiss the Sunset Pig: An American Road Trip With Exotic Detours (Penguin) a major theme of the book is my search for a cave I’d lived in when I was 21. The reason this story is in the Guardian now is because the editor at the Guardian asked if I happened to have any stories set in national parks. I said I didn’t think I did. Then later I realized I had a story about living in a cave. She liked that idea. I didn’t even tell her I’d actually written a whole book about it.