The London Underground

• Type: Muggle public transportation system
• Location: London, England
• Owner/Residents: Primarily owned and operated by Muggles; used by wizards and witches for inconspicuous travel within the city.
• Key Features: A vast subterranean network of electric railway lines, featuring stations with escalators, automatic ticket barriers, and distinctively tiled tunnels. It serves as an interface between the Muggle and wizarding worlds, notably providing access to the Ministry of Magic.

The London Underground, often referred to as the Tube by Muggles, is the primary rapid transit system serving the British capital. To the wizarding community, it is a fascinating, if sometimes bewildering, example of Muggle ingenuity. The system consists of deep, winding tunnels through which electric trains travel at high speeds, connecting various parts of the city. Stations are accessed via escalators or lifts, and passage is gained through automated ticket barriers, which can prove confusing for wizards unfamiliar with Muggle technology, such as Arthur Weasley. While it is a Muggle creation, the Underground is utilized by the magical community for discreet transportation. Its most significant connection to the wizarding world was the visitor's entrance to the Ministry of Magic. This entrance was located within a dilapidated red telephone box on a street near a busy Underground station in the heart of London. Visitors would dial the number 62442 (“MAGIC”) to be transported down into the Ministry's Atrium. Another notable, albeit unusual, connection is a scar on Albus Dumbledore's left knee, which he claimed was a perfect map of the London Underground.

The Underground appears at several key moments, often facilitating travel between the magical and non-magical parts of London.

• Harry Potter and the Philosopher's Stone: Rubeus Hagrid and Harry Potter use the Underground to travel from Paddington Station to the vicinity of the Leaky Cauldron on Charing Cross Road during Harry's first visit to Diagon Alley.
• Harry Potter and the Order of the Phoenix: The system plays its most prominent role when Arthur Weasley escorts Harry Potter to his disciplinary hearing at the Ministry of Magic. They navigate the Underground, with Mr. Weasley expressing great enthusiasm for its workings, particularly the ticket machines and escalators. They exit at a station deep in the city center to access the Ministry's visitor's entrance.
• Harry Potter and the Half-Blood Prince: While visiting the Dursleys, Albus Dumbledore casually mentions that he has a scar above his left knee that is a perfect map of the London Underground, highlighting his eccentric nature and familiarity with the Muggle world.
• Harry Potter and the Deathly Hallows: After the Ministry of Magic falls under the control of Lord Voldemort, the previous visitor's entrance accessible from the street is no longer used. When Harry, Ron Weasley, and Hermione Granger infiltrate the Ministry, they are forced to use a more direct, magical entrance via enchanted toilets, implying the old route via the Underground was sealed or abandoned by the new regime.

While a vast network, several specific stations and lines are relevant due to their proximity to important wizarding locations.

• King's Cross St. Pancras Station: A major interchange on the Underground, this station serves the mainline King's Cross Station from which the Hogwarts Express departs via Platform Nine and Three-Quarters.
• Paddington Station: Also an interchange station, used by Harry Potter and Hagrid in their first journey into wizarding London.
• Unidentified Station (Central London): The books describe Harry and Mr. Weasley exiting “at a station in the very heart of London” to reach the Ministry of Magic. The station is depicted as shabby and crowded.
• Charing Cross Road: The location of the Leaky Cauldron is served by multiple Underground stations, including Charing Cross and Leicester Square.

• In the film adaptation of Harry Potter and the Order of the Phoenix, the Underground station used to access the Ministry of Magic is explicitly identified as Westminster Tube Station. The filming took place at the actual station, which was closed to the public for a full day (film).
• J.K. Rowling has confirmed in an interview that Albus Dumbledore's scar is indeed just a map and does not possess any deeper magical significance. She stated, “It is the scar of a Muggle-lover, Dumbledore. He's not ashamed of it, he's proud of it.” (J.K. Rowling interview).