
The 57.1-km (35.5 mile)-long Gotthard Base Tunnel, 17 years under construction and designed to last a century, is part of a 23 billion Swiss franc infrastructure project to speed passengers and cargo by rail under the mountain chain that divides Europe's north and south.
Typically Swiss, the project that federal transport office director Peter Fueglistaler called "a masterpiece of timing, cost and policy" came in on schedule and on budget.
High-speed trains will whisk passengers in 17 minutes through a passage that took days until the first Alpine rail tunnel opened in 1882. Around 260 freight trains and 65 passenger trains will traverse the two-tube tunnel daily once final testing ends later this year.
With its official opening, the GBT has surpassed Japan's 53.9-kilometre Seikan tunnel as the world's longest train tunnel.
With political unity on the continent shaken by a massive influx of migrants and the looming threat of Britain's EU departure, Swiss president Johan Schneider-Amman said the tunnel would "join the people and the economies" of Europe.
He spoke before the 57-kilometre Gotthard Base Tunnel (GBT) made its ceremonial first run with European leaders on board. ?REUTERS