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Series 3 - World's Toughest Prison

World's Toughest Prison

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Documentary revealing the technological leaps forward that have enabled North Branch Correctional Institution in Maryland to become one of the most secure prisons in the world, holding over 1,400 of America's most dangerous prisoners.

The prison owes much of its innovation to the historic engineering breakthroughs at four earlier prisons - including the Tower of London and Alcatraz. Now, with its impenetrable cells able to withstand bomb blasts and technology ensuring dangerous inmates are kept safely away from each other, North Branch may be the toughest yet.

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