The Forbidden Mountain is where Maleficent's castle is located and where Maleficent used to reside in the 1959 film Sleeping Beauty. It is thought to be one of the gloomiest and darkest places to live. It's the place where Maleficent kidnapped Prince Phillip and locked him in her dungeon, in order to prevent him to rescue Princess Aurora and break the spell. The Three Good Fairies however, manage to sneak inside the castle and rescue him. They give him the Sword of Truth and the Shield of Virtue as he will encounter many dangers ahead. When Maleficent finds out that Prince Phillip has escaped, she does everything she can to prevent him by reaching the castle, abandoning her fortress in the process.
The Forbidden Mountain also appears as one of the basic locations, in the villains wars context.