J.K. Rowling said she first conceived Harry Potter during a delayed train journey from Manchester to London.
In accounts of the idea’s origin, Rowling described seeing the character of Harry Potter in her imagination while traveling in 1990. The train was delayed for several hours, giving her time to think about a boy who did not know he was a wizard. She later developed the setting, characters, and plot into the series of novels.
The journey’s destination was London, but the relevant city named in the origin story is Manchester, where the train had departed or was delayed. This detail is sometimes simplified as “on a train to London,” which leaves out the starting point.
Rowling did not immediately write the complete series. She spent years developing the manuscript and characters, and the first novel was eventually published in 1997. The train anecdote describes the initial idea, not the moment the first book was completed or sold.