The Hogwarts Express is a magical train in the Harry Potter series of books. It is ridden by students between London and Hogwarts. The train stops at Kings Cross station platform 9 3/4—which is invisible to Muggle eyes—and is reached through the barrier between platforms 9 and 10. Upon debarking from the train at Hogwarts, first years are treated to a ride across the lake by Hagrid, all other students are carried in coaches drawn by invisible (to most) creatures called thestrals.

Harry Potter met his two best friends Ron Weasley and Hermione Granger on his first ride on the Hogwarts Express. Harry Potter rode it nine times: twice a year for each of his first five years at Hogwarts except once, in Harry Potter and the Chamber of Secrets when he flew with Ron in a bewitched Muggle car, which crashed on landing and escaped into the woods. The car later saved him from the giant spiders . After each school year, Harry was met by his uncle and aunt after getting off the train; even though they hate him so much, they never failed to pick him up.

The Hogwarts Express is a steam train only in appearance and somewhat in function. The train is a magical device. It borrows its form and it's intended function from real steam trains, but not the technology.