Azkaban is supposedly one of the most inescapable locations in the Wizarding World. Guarded by Dementors and surrounded by water, the prison holds some of Britain's most dangerous wizards and witches, so when Sirius Black escapes after spending 12 years behind its walls in Harry Potter and the Prisoner of Azkaban, it initially seems like a far-fetched idea that he'd ever make it out in one piece.
