The grand Four Seasons is located just a date's throw from the Blue Mosque and the Topkapi Palace. However, it was once a prison housing dissident writers and politicians. Any hints of its former function are now limited to the imposing wooden doors at the entrance of the ochre-façaded hotel. Antique rugs and chandeliers fill the elegant interior while palm trees line the sun-filled courtyard.
Four Seasons Hotel, Tevkifhane Sokak No 1, Sultanahmet-Eminönü, Istanbul, Turkey (00 90 212 638 82 00; www.fourseasons.com/istanbul). Doubles from $343 (£196), including breakfast
In the incongruously leafy setting of Stockholm's seventh-largest island is a penitentiary that once enjoyed a certain notoriety. For close to 250 years, the island housed the biggest maximum-security prison in Sweden. It may be a hotel today but the stark architecture, watchtowers and inner courtyards reflect its past. The 102 rooms in the former Crown Prison are referred to as "cells" and are clean and comfortable, if somewhat small. A copy of an inmate's daily routine on the wall of each cell and a shop selling black and white striped T-shirts provide further reminders of its former life.
Langholmen Hotel, Langholmen Island, Stockholm, Sweden (00 46 8 720 85 00; www.langholmen.com). Double cells start at SKr1,240 (£88), including breakfast
An imposing Victorian edifice with a lengthy prison history is an unlikely candidate for a boutique hotel. But this has not stopped the hip Malmaison chain from taking residence in HM Prison Oxford. The building is part of Oxford Castle which dates back to 1071. Dark-wood panelling, exposed Victorian brickwork, tartan and tweed bedspreads and freestanding bathtubs boost the style factor throughout. But raised prison windows and original red cell-doors are constant reminders.
Malmaison, 3 Oxford Castle, Oxford (0845 365 4247; www.malmaison.com). Opens 28 November. Doubles from £110 without breakfast
There is little disguising the fact that Löwengraben was a prison until seven years ago. The interior belongs to the school of minimalist chic, with many of the original 1862 features taking centre stage. Iron beds, barred windows and wooden doors with food slots combined with clean lines and cream walls conspire to create the feeling of a modern, boutique hotel. The en-suite rooms range from the budget "quadro cell" for four people, to more luxurious suites, including one housed in the former library.
Jailhotel Löwengraben, Löwengraben 18, Lucerne, Switzerland (00 41 41 410 7830; www.jailhotel.ch). Doubles from Sfr54 (£24) excluding breakfast
Courthouse Hotel Kempinski London
In the Sixties, pop stars were prone to appear at the Great Marlborough Street magistrates' court on drugs charges; John Lennon and Mick Jagger spent time in its cells. Today, as the Courthouse Hotel, three cells remain in the bar. Thirteen suites are in the former judges' robing rooms. A police station, holding cells and a shooting range house 103 guest rooms. The number one court, where defendants included John Profumo and the Sex Pistols, is the Silk restaurant.
Courthouse Hotel Kempinski, 19-21 Great Marlborough Street, London W1 (020-7297 5555; www.kempinski.com). Doubles from £206 without breakfast