Extreme Constructions: Paris MetroTechnology, Travel|51:59
More than a century old, Paris' metro is the beating heart of the city. With its 220 km of rail, 302 stations and 13 lines, the metro transports more than five million people every day. Invented by Fulgence Bienvenüe, the Parisian Metro tested many construction methods: wooden tunnels, boring machines, shields, ground freezing systems, steel viaducts and submerged chambers in the Seine. Today, the Parisian metro exceeds the capitals boundaries and connects itself with the new 200km-wide network of Grand Paris Express.