Level Ten

• Type: Ministry of Magic Level
• Location: Deep underground beneath the Atrium of the Ministry of Magic, London, England
• Owner/Residents: Ministry of Magic; notably houses the Department of Mysteries and its staff of Unspeakables
• Key Features: Stark, windowless stone corridors; accessible only by lift; contains the entrance to the Department of Mysteries and the main Wizengamot courtrooms.

Level Ten is the deepest and most secure level of the Ministry of Magic. It is accessible via the main lift from the Atrium. The lift's announcement simply states, “Level Ten, Department of Mysteries.” Upon arrival, visitors find themselves in a bare stone corridor, devoid of windows or any doors aside from the one leading back to the lift. The corridor is torch-lit and has a chilly atmosphere. At the far end of this main corridor stands a single, plain black door without a handle or keyhole, which serves as the sole entrance to the Department of Mysteries. To the left of the lift exit, another corridor leads away to the Wizengamot courtrooms. Historically, Level Ten has been the site of major wizarding trials. In Harry Potter's fourth year, he witnessed memories in Albus Dumbledore's Pensieve showing the trials of Igor Karkaroff, Ludo Bagman, and the group of Death Eaters including Bellatrix Lestrange, all of which took place in Courtroom Ten on this level. During the Second Wizarding War, after the Ministry of Magic fell under the control of Lord Voldemort, these same courtrooms were repurposed for the unjust trials conducted by the Muggle-Born Registration Commission.

Level Ten is a location of significant legal and mysterious proceedings in the series, representing the core of the Ministry of Magic's power and secrets. In Harry Potter and the Order of the Phoenix, Harry Potter is unexpectedly brought to Courtroom Ten for his disciplinary hearing regarding his use of the Patronus Charm. The move, orchestrated by Cornelius Fudge, was intended to intimidate Harry and subject him to the full authority of the Wizengamot. Later in the same book, Level Ten serves as the gateway for Harry Potter and his friends when they infiltrate the Ministry to rescue Sirius Black, leading them through the black door into the Battle of the Department of Mysteries. In Harry Potter and the Deathly Hallows, the trio infiltrates the Ministry of Magic and witnesses the courtrooms on Level Ten being used by Dolores Umbridge and the Muggle-Born Registration Commission to persecute innocent Muggle-born witches and wizards. The location's role here highlights the complete corruption of the Ministry's judicial system under Voldemort's regime, turning a place of law into a chamber of prejudice and terror.

• Department of Mysteries: The most secretive department in the Ministry of Magic, located behind a plain black door at the end of the main corridor. It is comprised of a series of rooms dedicated to the study of profound mysteries like time, death, and love.
• Courtroom Ten: The primary courtroom for the Wizengamot. It is a dark, dungeon-like chamber with tiered stone benches for the court members and a single chair in the center for the accused, which is enchanted with chains that bind the occupant. This is where Harry's hearing was held and where the Muggle-Born Registration Commission later conducted its trials.
• Corridors: The level consists of stark stone corridors that connect the lift to the Department of Mysteries and the various courtrooms.

In the film adaptation of Harry Potter and the Order of the Phoenix, the design of Level Ten and Courtroom Ten is significantly expanded. The courtroom is depicted as a vast, circular, multi-storied chamber, with the defendant held in a suspended cage in the center, creating a more dramatic and intimidating visual than the dungeon-like room described in the novel (film).