The world’s longest tunnel, Switzerland’s 57-kilometer-long Gotthard Alpine rail crossing, broke through on Oct. 15. The Gotthard twin tunnels will be the longest of several being built through the Alps on the Milan, Italy, to Basel, Switzerland, corridor.
The joint-venture Tunnel AlpTransit-Ticino (TAT) broke northward from its Faido section of the east drive into the awaiting Sedrun stretch, roughly halfway along the tunnel. The west tunnel’s breakthrough is scheduled for next spring. TAT used 8.8-meter-dia Herrenknecht Gripper tunnel-boring machines for most of the excavation.