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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Any lingering showers clearing into tonight with a mostly dry but chilly night ahead. A cool but sunny start to Sunday.
Further heavy showers gradually clearing away this evening. Dry but chilly tonight, then dry with plenty of sunshine tomorrow.
Heavy showers turning potentially thundery this afternoon. Becoming dry but chilly tonight, then dry and sunny tomorrow.