The Gotthard axis consists of the Gotthard Base Tunnel, the partially operational Zimmerberg Base Tunnel, the Ceneri Base Tunnel (fully bored and in the process of being equipped) and surface connections. It is being built under contract from the Swiss Federal Government by AlpTransit Gotthard. The axis is the first flat trans-alpine rail link, with a maximum elevation of 550 metres (1,800 ft) above sea level.
This enables a high-speed link through the Alps with a top speed of 250 km/h (160 mph), reducing travel time between Zurich and Milan from four to – currently – three-and-a-half hours.

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Images: © Sacha Di Poi 2017

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