Girls' Lavatories at Hogwarts

While Hogwarts School of Witchcraft and Wizardry contains numerous lavatories for its students, two specific girls' lavatories serve as the settings for pivotal events in the series. The first-floor girls' lavatory is most famous for housing the secret entrance to the Chamber of Secrets and for being haunted by Moaning Myrtle. A separate girls' lavatory on the sixth floor is the site of a violent duel between Harry Potter and Draco Malfoy.

• Type: Lavatory, Secret Entrance
• Location: First Floor, Hogwarts Castle
• Residents: Myrtle Warren (Moaning Myrtle)
• Key Features: Entrance to the Chamber of Secrets, perpetually out-of-order, haunted.

This lavatory is depicted as a gloomy and disused facility. It is seldom, if ever, used by students due to its dilapidated state—featuring cracked mirrors and constantly dripping taps—and the presence of its resident ghost, Moaning Myrtle. One of the copper taps on a row of scratched stone sinks is unique; it has a tiny snake engraved on its side. This tap serves as the lock to the Chamber of Secrets. Speaking Parseltongue to it causes the sink to sink into the floor, revealing a large pipe leading down to the Chamber. The entrance to the Chamber was created by Salazar Slytherin himself. According to Hogwarts history, when plumbing was introduced to the castle in the eighteenth century, Slytherin's descendant Corvinus Gaunt preserved the secret entrance by skillfully incorporating it into the new pipework. On 13 June 1943, a student named Myrtle Warren was killed in this lavatory after looking into the yellow eyes of the Basilisk released by Tom Riddle. Her ghost has haunted the bathroom ever since, earning her the nickname Moaning Myrtle and ensuring the lavatory remains largely abandoned.

• Harry Potter and the Chamber of Secrets: Due to its disuse, the lavatory becomes the trio's headquarters for brewing the Polyjuice Potion. It is here that Hermione Granger has an accident with cat hair, mistaking it for that of Millicent Bulstrode. Later, Harry Potter and Ron Weasley learn from Myrtle the details of her death. Harry subsequently opens the Chamber of Secrets here, descending with Ron and an unwilling Gilderoy Lockhart to rescue Ginny Weasley.
• Harry Potter and the Deathly Hallows: During the Battle of Hogwarts, Ron re-opens the Chamber by mimicking the Parseltongue sounds Harry made, allowing him and Hermione to retrieve Basilisk fangs. They use a fang to destroy the Horcrux, Helga Hufflepuff's Cup.

This lavatory is much larger and more elegant than the one on the first floor, containing handsome marble washbasins. Moaning Myrtle also frequents this location, often to comfort unhappy students. Its primary significance occurs in Harry Potter and the Half-Blood Prince. Harry Potter follows Draco Malfoy here and finds him crying, being comforted by Myrtle. Their confrontation escalates into a fierce duel. When Malfoy attempts to use the Cruciatus Curse, Harry defensively casts Sectumsempra, a dark curse he discovered in the Half-Blood Prince's copy of Advanced Potion-Making. The spell inflicts deep, life-threatening wounds on Malfoy, who is saved only by the swift intervention of Severus Snape.

• J.K. Rowling revealed that Hogwarts was built without bathrooms. Witches and wizards of the time simply relieved themselves where they stood and used magic to vanish the evidence. Plumbing was added in the eighteenth century. (Pottermore)
• In the film adaptation of *Harry Potter and the Chamber of Secrets*, the first-floor lavatory is depicted as a very large, circular room with sinks arranged around a central stone pillar. The entrance to the Chamber is activated when the snake engravings on the taps retract, causing the entire sink structure to lower and reveal the entrance pipe. This is a significant visual departure from the book's description of a single sink in a row moving away. (film)