Эпизод 3

Beneath the streets of London, lies a parallel universe. As its buildings soar higher, so its tunnels go deeper. London has more infrastructures built underground than any city in the world. They hold the key the city's success. This episode strips away the ground to reveal the city's inner workings and explores the ingenious technologies that helped engineers to build one of the biggest cities on Earth. We join engineers working in this vast underground city - from tunnel builders digging a brand new underground train line 40m beneath the city to squads of workers scrubbing its sewer tunnels to prevent outbreaks of disease. We lift up Buckingham Palace to reveal a "lost" river and show the innovative engineering behind the city's brand new port under construction. We peel away the Tower of London to reveal the true scale of the river Thames - far from being quiet and obedient, it was once a tidal torrent. And we strip back the steel and glass from Europe's tallest skyscraper - the Shard - to reveal its hidden inner workings. This episode explores the geology that shaped the city's past and challenges its future, from the rich clay that it sits on to the river that may one day consume it.