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First broadcast at 20:00 11 Jul 2012
A fascinating look at the great engineering leaps that built the London Underground, the biggest metro system in the world.
Discover the history of trains and the engineering breakthroughs from the Rocket to the TGV.
Documentary about the North Branch Correctional Institution, one of the most secure prisons in the world.
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Channel 5 Broadcasting Ltd. 2014
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