Return of the super-prison as the Coalition changes tack Mr Grayling is expected to tell MPs he is starting a feasibility study for the project which would house 2,000 inmates in one jail. Four mini-prisons, with an extra 1,000 places in total, will also be built over the next two years as smaller and more expensive jails are closed, it is understood. Projections from the Ministry of Justice show the population could rise as high as 90,900 in the next five years. Sites being considered for the super-jail are understood to be in London and the North West or North Wales. The plans are likely to cause concerns for prison governors and penal reform groups who claim that large prisons are difficult to control and would result in inmates being "warehoused." Britain's largest jail, the Victorian Wandsworth Prison in south London, can hold 1,665 prisoners while the new Oakwood Prison in Featherstone near Wolverhampton, run by G4S, opened last year with places for 1,605. An inspection of Wandsworth raised serious concerns, adding there was "no doubt it holds a challenging population with multiple problems." Plans to build Britain's biggest jail will also evoke memories of Labour's £2.9 billion proposal for three 2,500-capacity Titan jails, which was scrapped in 2009. Juliet Lyon, of the Prison Reform Trust, said that with crime levels falling "the only reason to revive the debunked idea of Titan prisons would be for political capital." "It would be a gigantic mistake if the Justice Secretary were to pour taxpayers" money down the prison-building drain."