World's longest and deepest rail tunnel opens in Switzerland
A tunnel through the Alps in Switzerland that has taken 17 years to build officially opens today. The Gotthard Base Tunnel stretches for 57 km (35 mi), making it the longest rail tunnel in the world. In addition, at 2,300 m (7,546 ft) below the surface of the mountain in places, it is also the world's deepest rail tunnel.
