The world’s longest tunnel officially opened with the trailblazing rail passage under the Swiss Alps aiming to ease transit through the heart of Europe.  The 57km (35-mile) twin-bore Gotthard base tunnel will provide a high-speed rail link under the Swiss Alps between northern and southern Europe. Switzerland says it will revolutionise European freight transport.

Goods currently carried on the route by a million lorries a year will go by train instead. The tunnel has overtaken Japan’s 53.9km Seikan rail tunnel as the longest in the world and pushed the 50.5km Channel Tunnel linking the UK and France into third place.

The project, which cost more than $12bn to build, was endorsed by Swiss voters in a referendum in 1992. Voters then backed a proposal from environmental groups to move all freight travelling through Switzerland from road to rail two years later.

The completed tunnel travels up to 2.3 km below the surface of the mountains above and through rock that reaches temperatures of 46C. Engineers had to dig and blast through 73 different kinds of rock, some as hard as granite and others as soft as sugar. More than 28m tonnes of rock was excavated, which was then broken down to help make the concrete used to build the tunnel.

Now the completed tunnel, delivered on time and within budget, will create a mainline rail connection between Rotterdam in the Netherlands and Genoa in Italy.

When full services begin in December, the journey time for travellers between Zurich and Milan will be reduced by an hour to two hours and 40 minutes.