Justice Secretary Chris Grayling has said the announcement of four prison closures and two new "super" prisons was part of a "process of new for old in the prison system" aimed at creating more places.
He said a new prison in Wrexham would be Britain's "biggest prison" and would meet the need for capacity in north wales, and a shortage of places in the north west.
Mr Grayling said there was no plan for so-called "titan" prisons, with one single big building holding thousands of prisoners, and added that the new jails would be a spread out over a "campus" of individual blocks holding a few hundred prisoners, with shared facilities.
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