The Elizabeth Arkham Asylum for the Criminally Insane is a psychiatric institution located on the outskirts of Gotham City in the DC Comics universe.
Arkham Asylum is the only facility near Gotham City equipped to contain and treat super-villains who have been judged guilty by reason of insanity. While its most infamous resident is the paste-faced criminal mastermind known as the Joker, Arkham Asylum's inmate roll call has also included the Riddler, Mr. Freeze, Poison Ivy, and former Gotham City district attorney Harvey Dent.
All of these super-villains have been imprisoned in and escaped Arkham, repeatedly. On one occasion, the inmates literally took over the asylum. The Joker, Two-Face, Poison Ivy, and others demanded the Batman turn himself over to him in exchange for hostages.3
As an important part of the Batman mythology, Arkham Asylum has been featured in a number of movies, animated features, and other media. The institution is included in the films Batman Forever, Batman and Robin, Batman Begins, and The Dark Knight. Arkham Asylum is a repeated setting in episodes of Batman: The Animated Series, Justice League, Batman Beyond: Return of the Joker and The Batman. LEGO even created an Arkham Asylum playset.