Azkaban

Azkaban is a prison for criminals of the British and Irish wizarding world. According to Half-Blood Prince, Azkaban is located somewhere in the North Sea. It is guarded by Dementors, which render the inmates incapable of happiness. According to Sirius Black, many inmates simply stop eating and eventually die of starvation. It was considered impossible to escape from Azkaban until Sirius managed to do it. Performing any of the Unforgivable Curses on a human is punishable by a life sentence in the prison, although there are occasions when Aurors are allowed to perform those curses. Following Voldemort's demise, Kingsley Shacklebolt becomes Minister of Magic and ends the use of Dementors at Azkaban.