NRLA

AlpTransit, also known as New Railway Link through the Alps, NRLA (German: Neue Eisenbahn-Alpentransversale, NEAT, French: nouvelle ligne ferroviaire à travers les Alpes, NLFA, Italian: Nuova ferrovia transalpina, NFTA), is Switzerland's largest-ever construction project for faster north-south rail links across the Swiss Alps by constructing a series of base tunnels several hundred metres below the current tunnels. For safety, all the tunnels have two parallel single-track bores joined about every 300 metres with cross cuts, enabling the other tunnel to be used for escape. The $13 billion project consists of two major sections, the Gotthard axis and the Lötschberg axis, which respectively include the 57-kilometre (35 mi) long Gotthard Base Tunnel and the 35 km long Lötschberg Base Tunnel, respectively. The centrepiece, the Gotthard Base Tunnel, became operational on 11 December 2016, and the Ceneri Base Tunnel is scheduled to become operational in 2020.

The Gotthard axis consists of the new Gotthard Base Tunnel, the partly operational Zimmerberg Base Tunnel, the Ceneri Base Tunnel which is fully bored and now being equipped, and some surface connections. It is being built under contract from the Swiss Federal Government by the company AlpTransit Gotthard AG. The new axis will be the first flat transalpine rail link with a maximum elevation of just 550 metres (1,800 ft) above sea level. This results in 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 the previous 4h00 to 2h30.

At 57-kilometre (35 mi) long, the Gotthard Base Tunnel is the world's longest railway tunnel, as the original Gotthard tunnel of 15 kilometres (9.3 mi) was at the time of its 1881 completion. The new one consists of two 57-km long tunnels, each with one train track. The two tunnels are connected by 178 cross connections. It has two emergency stop platforms in each tunnel, they are connected with the emergency stop platform of the opposite tunnel. These stations are equipped with water refilling equipment to refill the firefighter and rescue train. One of these stations was proposed as an extremely deep railway station, called Porta Alpina, but that option was eventually rejected on both economical and technical grounds. The completed tunnel was handed over by AlpTransit Gotthard AG to the Swiss government on 31 May 2016. It was formally opened in a ceremony the following day, during which the tunnel was conveyed to its operator, the Swiss Federal Railways (SBB CFF FFS).

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Wikipedia