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Earlier this week, the new longest tunnel in the world was completed. The Gotthard Base Tunnel started in 2004, and travels underneath the Swiss Alps for 35.4 miles. The cost of the project was just under $10 billion U.S., and now it is finally done, though it won't see its first passenger trains until next year.
The Gotthard Base tunnel was constructed some 2,000 feet below an existing 10 mile tunnel that was opened in 1882. In addition to accommodating more trains through the mountain range on its two parallel one-track tubes, the new tunnel is rated to handle a whole lot more weight. It can handle trains up to 4,000 short tons, more than twice that of its predecessor.
To dig the extremely long tunnel, miners used an army of mining machines three stories high and over 1,200 feet long, drilling from both sides. They finally met in the middle in 2010, and the last bit of track was laid down on October 31st of 2014.
The next step is to begin testing the tunnel's ventilation, communication infrastructure, and of course the tracks along which trains will barrel at speeds of up to 150 miles per hour. The testing begins in October and if all goes well—so far it has; the project has suffered no large delays—the first passenger trains will blast through it on June 1st, 2016. This is one tunnel you'll have no hope of holding your breath all the way though.
Source: TDG via Business Insider
