Seventeen years of construction on the world’s current longest tunnel, through the Alps, formally ends on June 1, when the Swiss Federal Railways takes charge of the 57-kilometer-long, twin-bore Gotthard base tunnel. With two of the three major tunnels of the New Railway Link through the Alps (NRLA) program now done, only the 15.4-km-long Ceneri base tunnel is still being built.
Since starting the Gotthard work in May 2003, four TBMs displaced some 10.5 million cu meters of rock while boring 75% of the 150 km of tunnel drives—the rest was by drill-and-blast. A $1.7-billion railroad-systems contract followed the civil work, leading to this week’s handover before heads of state and other dignitaries.