Switzerland has completed construction on a 35-mile tunnel -- the world's longest

The Swiss Alps are an unforgiving landscape of rugged, rocky peaks and lush, green valleys. Connecting communities that would be otherwise isolated by the vast mountain range — including cultural and economic hubs like Zurich, Milan and Turin — is no easy task.

Tunnelling and track-laying for the 35-mile NEAT Gotthard Base Tunnel has been completed, making it officially the longest tunnel in the world, surpassing Japan’s 14.5-mile Seikan Tunnel.

Swiss authorities held a media day inside the tunnel on August 24 to announce that the majority of technical work for the tunnel had been completed, Swiss newspaper TDG reports. Testing will begin October 1 in anticipation of the first passenger and freight trains in June 2016.

Europe's most densely populated belt, historically known as the 'blue banana,' stretches from Northern England, south through the Netherlands, Switzerland, France, and Germany, and into northern Italy.

Wikimedia Commons

The first tunnel on the Gotthard axis, connecting Zurich and Milan by train, was completed in 1882 as a joint venture by Switzerland, Germany and Italy, all of which benefit from trade along the vital North-South route.

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Travel time between Zurich, Lugano and Milan will be shortened by an hour once the tunnel opens to passenger service in June 2016.

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Trains will speed through the tunnel at over 150 miles per hour. This is only possible because the tunnel grade is almost completely flat throughout its entire length. Much more level than the alpine peaks above.

AlpsTransit

Laying track in the tunnel has been much quicker than the previous boring stages (pun intended). On October 31, 2014, workers celebrated laying the final track segment with what they call a 'golden sleeper.'

AlpsTransit

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