Switzerland will inaugurate the opening of the world’s longest and deepest train tunnel next week which, when complete, will help reduce travel times between cities by up to a full hour.

After 17 years of construction work, the Gotthard Base Tunnel will open for the first time June 1, extending 57 km in length into the bowels of the earth 2,300 meters below the Gotthard massif in the Swiss Alps.

With speeds reaching up to 250 km/hr, the travel time from one end of the tunnel to the other will take just 20 minutes.

Worlds Largest Tunnel

By December, when the tunnel is fully operational, passengers can expect to reduce their travel time on routes such as Milan to Zurich, and Basel to Lugano by between 25 to 40 minutes.

Once the Ceneri Base Tunnel enters operation, travel times are expected to be slashed by a full 60 minutes by 2020.

That means that instead of a four-hour train journey between Milan and Zurich, for example, travel times will be cut down to three hours.

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Other than the 20 minutes spent speeding through the underground tunnel, the existing Gotthard rail route is known for offering sweeping views of the Swiss Alps, from the forests of firs in the mountains to the palms and stone dwellings in the south of the country.

The rail route takes travelers over 250 bridges and seven loop tunnels.

Gotthard massif Swiss Alps

Highlights of the Gotthard rail route include some of the highest bridges on the national railway network, including the Chärstelenbach Bridge (127 m) and the Intschireuss Bridge (121 m), as well as a double loop tunnel which offers views of the Baroque church of Wassen from three different perspectives.

Other scenic train journeys created to showcase Switzerland’s landscape under Grand Train Tour of Switzerland program include the Glacier Express, an eight-hour journey that travel deep into the Alps; the Bernina Express which links the north and the south; and the GoldenPass Line, which takes travelers through three regions, and along eight lakes.

The Gotthard Base Tunnel enters into regular operation on December 11, 2016.

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