Switzerland has just opened Gotthard Base Tunnel (GBT). The tunnel is 35.4 miles in length and is located 7545 feet below the Gotthard massif, through Swiss Alps. The tunnel is said to provide a high-speed rail link between northern and southern Europe under the Swiss Alps.
The idea has been under consideration since 1947 but the construction started 18 years ago. The project cost more than $12bn (£8.3bn) to materialize and was endorsed in 1992 by Swiss voters in a referendum.
The Gotthard Base Tunnel (GBT) stretches up to 2.3 km under the mountains and rocks, some of them having temperatures upto 46 degree Celsius.
The site engineers had to dig and blast their way out through 73 different kinds of rocks. Almost 28m tonnes of rock had to be excavated which was later used to make concrete for building the tunnel.
The tunnel can accommodate 260 freight trains and 65 passenger trains and is being financed by fuel taxes, road charges and state loans that are due within a decade.