The UK Justice Secretary, Chris Grayling, says the prison which will be built in north Wales will be 'Britain's biggest'.
He says the announcement is a very important part of upgrading Britain's prisons.
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This week Carl talks to psychologist Amy McClelland about new research on the sleeping habits of babies.
For those who have mobility problems the idea of a walk in the Welsh mountains may seem unlikely. But this new scheme may change that.
Any rain will eventually clear this afternoon, bringing brighter weather behind it.