Miners in central Switzerland have pierced a first stage of the new tunnel through the Gotthard, which is set to become the longest rail tunnel in the world.
The 57km-long tunnel on the main north-south transalpine route is part of a major upgrade of Swiss rail transit infrastructure and is due to open for traffic in 2016.
The breakthrough in the tunnel section between Faido and Bodio on Wednesday came after four years of work. The giant boring machine reached its target with a precision of a few centimetres.
The work was delayed by 17 months because the drill had to pass through difficult geological rock formation in the 13.5km tunnel section.
"It is a mere pin prick for the mountain, but a breakthrough for mankind," said Peter Zbinden, head of the construction company AlpTransit, at a ceremony attended by more than 1,000 guests.
Zbinden pointed out that the new Gotthard tunnel was a key element of the main transalpine rail link. He said the aim was to bring as much of the road freight traffic on to rail and promote Switzerland's most sustainable environment project.
A breakthrough in the second tube on the same section is expected next month. But the whole tunnel is not expected to open for rail services before 2016.
Officials say just under 99km of the total 153.5km-long tunnel system, including shafts and galleries, had been excavated by the beginning of September, with around 2,200 miners working on the construction sites.
Work, which is underway at seven different sites, began after a nationwide vote in 1998.
The first rail tunnel through the Gotthard, which is 15km long, was inaugurated in 1882, while the Gotthard road tunnel was opened in 1980.
swissinfo with agencies
The upgrade of the country's rail network includes the construction of two new tunnels - in central Switzerland (Gotthard) and western Switzerland (Lötschberg).
The aim is to transfer transiting freight traffic between Germany and Italy from road on to rail.
Excavation work, including a shaft for the world's tallest elevator, began on the southern entrance, tunnelling has yet to start at the northern section.
Total length: 57.1km
Open for traffic: 2016
Beginning of construction: 1993 (test drillings), 1996 (preparations), 2003 (mechanical excavation)
Total cost: about SFr8 billion($6.4 billion)
Volume of excavated rock: 24 million tons
Construction progress (Sept 2006): 98.8km
The Gotthard - Europe's alpine axis
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