BBC: The world's longest and deepest rail tunnel has officially opened in Switzerland, after almost two decades of construction work.
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...