The Slytherin Common Room

• Type: `Common Room`
• Location: The `Hogwarts Dungeons`, beneath the `Great Lake`, `Hogwarts School of Witchcraft and Wizardry`, `Scotland`
• Owner/Residents: Students of `Slytherin` House; overseen by the Head of House (primarily `Severus Snape`, and later `Horace Slughorn`)
• Key Features: Dungeon-like atmosphere, underwater location, greenish lighting, entrance concealed behind a stone wall, requires a `Password` to enter.

Founded by `Salazar Slytherin`, the `Slytherin` common room's design reflects its founder's affinity for water and serpentine `creatures`. The entrance is located in the `Hogwarts Dungeons`, concealed behind a bare, damp stretch of stone wall. Entry is granted only after speaking the correct `Password` to the wall, which causes a stone door to silently slide aside. The common room itself is a long, low-ceilinged, dungeon-like chamber. Its location directly beneath the `Great Lake` gives the room a distinctive, watery green light, which emanates from green lamps hanging by chains from the ceiling. The walls and ceiling are made of rough-hewn stone. The room is furnished with low-backed, black and dark green leather sofas and chairs with silver studs, and features a grand fireplace with an elaborately carved mantelpiece. The windows of the common room look out directly into the murky green depths of the `Great Lake`. Students can observe the lake's various inhabitants, including the `Giant Squid` and the `Grindylow`s, as they swim past. The overall atmosphere is one of cold, underwater grandeur. A notice board is also present, used for official `Hogwarts` decrees and house-specific information, such as the notice for the formation of the `Inquisitorial Squad`.

• Harry Potter and the Chamber of Secrets: The common room features most prominently when `Harry Potter` and `Ron Weasley` use `Polyjuice Potion` to disguise themselves as `Gregory Goyle` and `Vincent Crabbe`. They successfully infiltrate the room to question `Draco Malfoy` about his potential role as the `Heir of Slytherin`. It is here they learn that Malfoy is not the heir and discover that the `Chamber of Secrets` was last opened fifty years prior, leading to the death of a `Muggle-born` student.
• Harry Potter and the Order of the Phoenix: The room serves as the unofficial headquarters for the `Inquisitorial Squad`, a group of students empowered by `Dolores Umbridge` and comprised mostly of `Slytherin`s, led by `Draco Malfoy`.
• Harry Potter and the Half-Blood Prince: While not visited directly by Harry, the common room is the base from which `Draco Malfoy` operates for much of the year while working to repair the `Vanishing Cabinet`. He is believed to have used the `Imperius Curse` on `Crabbe` and `Goyle` here to make them act as his lookouts.
• Harry Potter and the Deathly Hallows: Prior to the `Battle of Hogwarts`, the `Slytherin` students are evacuated from the `Great Hall` and led down to the `Hogwarts Dungeons`, presumably to be secured in their common room, to prevent them from joining `Lord Voldemort`'s forces.

• The main chamber, which serves as the central lounge area with a fireplace.
• An entrance corridor behind the sliding stone door.
• A notice board for announcements.
• Separate doors leading to the boys' and girls' `dormitories`.

• On the Pottermore website, J.K. Rowling described the room as having a “mysterious, underwater shipwreck-like quality,” and mentioned that the walls are hung with green silk tapestries decorated with silver thread, depicting the adventures of famous medieval `Slytherin`s. (Pottermore)
• In the film adaptation of Harry Potter and the Chamber of Secrets, the set for the `Slytherin` common room was designed to be vast and cavernous, far larger than the “low-ceilinged” room described in the novel. The set featured imposing stone columns, massive snake sculptures, and a grander, more palatial atmosphere to reflect the house's ambition and connection to wealth. (film)
• The `Slytherin` common room is an accessible and key location in numerous `Harry Potter` video games, including the Harry Potter and the Chamber of Secrets game and, more recently, Hogwarts Legacy, where its design often blends elements from both the books and the films. (video game)