Geneva (AFP) - The new Gotthard Base Tunnel (GBT), set to become the world's longest railway tunnel when it opens on June 1, is a "godsend for Europe", EU transport commissioner Violeta Bulc told Swiss media Monday.
The 57-kilometre (35.4-mile) tunnel, which runs under the Alps, was first conceived in sketch-form in 1947 but construction began 17 years ago.
Since then, some 28.2 million tonnes of mountain rock have been excavated and an estimated $12 billion (10.6 billion euros) spent to construct a tunnel that should trim travel times through the heart of Europe.
The GBT "will be a vital link connecting Rotterdam (and) Antwerp with the ports of the Adriatic," Bulc told the Swiss daily Tages Anzeiger.
It will make north-south travel more fluid, curb air pollution and "will be a driver of growth in Europe," the Slovenian national was further quoted as saying.
German Chancellor Angela Merkel, French President Francois Hollande and Italian Prime Minister Matteo Renzi, along with Swiss officials, are due to attend the grand opening next week.
A series of test runs are scheduled for the coming months, with full service starting in December.
Among other benefits, the GBT aims to shave travel time between Zurich and Milan down to two hours and forty minutes, roughly an hour quicker than the trip currently takes by rail.
The GBT will displace Japan's 53.9-kilometre Seikan tunnel as the world's longest train tunnel, and bump the 50.5-kilometre Channel Tunnel that links England and France into third place.
Austria's delayed Brenner Tunnel could however slot into second place when it opens in about a decade at an estimated length of 55 kilometres.