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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Friday's GMB weather for the west of the region
Friday's GMB weather for the east of the region
David Browning said Jillian Howell screamed “you b******”, to which he replied: “I’m sorry Jill, this is what mental health does to you.”