On an island in the middle of the North Sea lies the Unplottable fortress that is Azkaban prison. With the creator of the fortress, Ekrizdis, long gone, the Ministry of Magic began using the island as a detention facility in 1718 and continues to use it as such to this very day. There once was an infestation of Dementors that once roamed free here; however, after a number of mass breakouts due to the creatures revolting and joining Lord Voldemort, Aurors have been taking shifts to guard the prison in an effort to prevent another mass breakout from occurring.

The island itself is surrounded by iron walls and has a very minimalistic layout, containing a burial ground, for bodies unclaimed, and a tall tower. The tower is dark and contains hundreds of cells for criminals of varying sentences. Most of the prison's cells are big enough to hold two to four people. Those with long-term sentences, however, are placed in small high-security cells, which are bound with the most complex of enchantments.

Visitors, typically respectable Ministry employees and an inmate's immediate family, need to be pre-approved and then go through numerous security checks upon arrival. From there, visitors are seated in a drab visiting room where a number of Aurors stand guard. Prisoners arrive wearing charmed straightjackets and are promptly returned to their cells when the time allotted for a visit is up.