Tunnel Mastery – Extreme Excavation – Big Bigger Biggest

Documentary revealing the technological leaps behind the world’s longest and deepest railway tunnel, the Gotthard Base Tunnel. It stretches over 57 kilometres through the heart of the Swiss Alps. At a depth of 2,300 metres, it’s deeper than any other tunnel on Earth, providing a vital highspeed rail link between Zurich and Milan. We follow 2,000 workers and four gigantic tunnel boring machines working flat-out to excavate 24 million tonnes of mountain rock to complete the tunnel. This film explores how this structure was made possible through a series of engineering breakthroughs. Six landmark tunnels, including the Thames Tunnel and Channel Tunnel, each feature a major technological innovation that allowed engineers to bore ever further into the Earth. Using computer generated animation we reveal the incredible stories behind these tunnels and the inventions that have enabled tunnels to grow ever longer. Six ingenious leaps forward that enabled tunnels to evolve from BIG, to BIGGER, into the world’s BIGGEST. 00:00 – Introduction 03:50 – Collapse – Thames Tunnel 13:31 – Blasting – Box Tunnel 21:23 – Machine Boring – Mersey Tunnel 28:34 – Ventilation – Simplon Tunnel 36:45 – Precision – Channel Tunnel 45:14 – Safety – Gotthard Base Tunnel Episode from the “Big Bigger Biggest” documentary series exploring the engineering breakthroughs that have enabled us to develop some of the largest structures in existence. Subscribe to Element 18 – https://bit.ly/337R2uO