Tunnel structure

The Ceneri Base Tunnel was excavated entirely by drilling and blasting. The minimum depth of overlying rock is only a few metres.

Most of the excavation was performed simultaneously in both directions from the intermediate heading at Sigirino. Inward drives were also cut from the portals at Vigana and Vezia.

Driving to the south progressed faster than forecast. In the west tube, breakthrough to the inward drive from Vezia already took place on March 17, 2015. This was 13 months ahead of the construction schedule! On January 21, 2016, the miners and many invited guests could celebrate the final breakthrough of the Ceneri Base Tunnel in the west tube. The breakthrough took place with great accuracy: the vertical deviation was less than 2 cm, horizontally it was not even 1 cm.