What is the name of the prison island where Arkham Asylum is located?

The prison island where Arkham Asylum is located is called Arkham Island. In Batman: Arkham Asylum, the island is an isolated facility off the coast of Gotham City and serves as the game's primary setting after the Joker seizes control of the asylum.

Arkham Island is more than a single building. It contains the main asylum complex along with grounds, medical and penitentiary areas, abandoned structures, underground passages, and restricted zones. Batman must move between these locations while tracking the Joker, investigating criminal activity, rescuing hostages, and uncovering the effects of the Titan drug.

Players often confuse Arkham Island with locations from later games. Batman: Arkham City takes place in a fortified section of Gotham known as Arkham City, while Arkham Knight spans several Gotham islands, including Bleake Island, Miagani Island, and Founders' Island. Blackgate Island is associated with Blackgate Penitentiary, a different prison facility. Those names belong to other locations, so Arkham Island is the specific answer for Arkham Asylum.