Brenner Base Tunnel completes first 55km main tube

The Brenner Base Tunnel (BBT) project has reached a major milestone with the completion of the first continuous main tunnel tube. The western main tunnel, stretching approximately 55 kilometers from the Sills Gorge near Innsbruck to Franzensfeste in South Tyrol, has been successfully connected.

The feat was achieved by the tunnel boring machine ‘Wilma’, which was in operation for 706 days after starting on September 18, 2024. The massive machine, measuring 180 meters in length and weighing 2,700 tons, navigated through challenging geological fault zones to complete the drive.

Project logistics played a critical role in the success of the operation. By utilizing rail transport for the delivery of tunnel linings (tubbings) and managing material removal via conveyor belts, the project managed to save approximately 45,000 truck trips that would have otherwise been required for road transport.