The world's longest and deepest rail tunnel is to be officially opened in Switzerland, after almost two decades of construction work.
When Swiss engineer Carl Eduard Gruner came up with the idea to build the world's longest rail tunnel under the Alps in 1947, he predicted the visionary project could be finished by the start of the 21st century.
The world's longest and deepest rail tunnel is to be officially opened in Switzerland, after almost two decades of construction work.
When Swiss engineer Carl Eduard Gruner came up with the idea to build the world's longest rail tunnel under the Alps in 1947, he predicted the visionary project could be finished by the start of the 21st century.