It's an experience most of us try to avoid, but hundreds of people have taken up the rare opportunity to get a taste of life behind bars.
They were on a series of guided tours around Kingston Prison in Portsmouth which closed earlier this year. What impression did they get of what it would have been like for the inmates? Richard Jones was there to find out.
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Jenny Fry, 15, claimed she had electro-hypersensitivity (EHS) which caused her to suffer tiredness, headaches and bladder problems.
Doctors have recommend Peter Sutcliffe be moved to high security prison, but the final decision will be taken by the justice secretary.
An investigation has seen four men jailed for a total of more than 17 years after importing more than 60kg of cannabis resin.