Para os magos britânicos, a resposta parece ser que não há alternativas para Azkaban se você estiver preso.
Tudo começou quando o Estatuto Internacional de Sigilo foi imposto. Parecia que as prisões menores e menos protegidas eram mais fáceis de escapar e atraíam a Atenção aos Trouxas, como seria de se esperar com uma mangueira fazendo mágica.
Once the International Statute of Secrecy had been imposed, the Ministry of Magic felt that the small wizarding prisons that existed up and down the country in various towns and villages posed a security risk, because attempts by incarcerated witches and wizards to break out often led to undesirable bangs, smells and light shows. A purpose-built prison, located on some remote Hebridean island, was preferred, and plans had been drawn up when Damocles Rowle became Minister for Magic.
Azkaban forneceu uma solução eficaz aparentemente independente do crime cometido.
In spite of opposition from many wizards, among them experts on both Dementors and buildings with Azkaban’s kind of Dark history, Rowle carried out his plan and soon a steady trickle of prisoners had been placed there. None ever emerged. If they were not mad and dangerous before being placed in Azkaban, they swiftly became so.
ibid
Uma vez que começou a fazer isso, efetivamente, apenas um Ministro da Magia (até Shacklebolt) já olhou para uma alternativa, mas já era tarde demais. Além disso, havia um temor de que os dementadores deixassem a ilha à procura de mais almas para se alimentar.
Rowle was succeeded by Perseus Parkinson, who was likewise pro-Azkaban. By the time that Eldritch Diggory took over as Minister for Magic, the prison had been operating for fifteen years. There had been no breakouts and no breaches of security. The new prison seemed to be working well. It was only when Diggory went to visit that he realised exactly what conditions inside were like. Prisoners were mostly insane and a graveyard had been established to accommodate those that died of despair.
Back in London, Diggory established a committee to explore alternatives to Azkaban, or at least to remove the Dementors as guards. Experts explained to him that the only reason the Dementors were (mostly) confined to the island was that they were being provided with a constant supply of souls on which to feed. If deprived of prisoners, they were likely to abandon the prison and head for the mainland.
This advice notwithstanding, Diggory had been so horrified by what he had seen inside Azkaban that he pressed the committee to find alternatives. Before they could reach any decision, however, Diggory caught dragon pox and died. From that time until the advent of Kingsley Shacklebolt, no Minister ever seriously considered closing Azkaban. They turned a blind eye to the inhumane conditions inside the fortress, permitted it to be magically enlarged and expanded and rarely visited, due to the awful effects of entering a building populated by thousands of Dementors. Most justified their attitude by pointing to the prison’s perfect record at keeping prisoners locked up.
ibid
Para outros países, parece haver outras prisões ... ou pelo menos uma que conhecemos.
Sabemos que Gellert Grindelwald foi preso na prisão de Nurmengard quando Voldemort o encontrou.