The breakthrough occurred on the stroke of noon with the final blast taking place in the western tube of the southern section between the intermediate access tunnel at Sigrino and the southern portal at Vezia, with a deviation of only 1cm vertically and 2cm horizontally.

Breakthrough on the eastern bore is expected at the end of March. Work on the northern section of the tunnel, between the intermediate access tunnel at Sigrino and Vigana, is less advanced – with breakthrough expected at the beginning of next year. Most of the tunnelling work is being carried out using traditional drilling and blasting techniques.

"This first breakthrough in the Ceneri Base Tunnel is a further important milestone in the construction of the New Rail Link through the Alps (NRLA)," says Mr Renzo Simoni, CEO of Alptransit Gotthard. "Alptransit is doing its utmost to make sure it achieves its goal of opening the tunnel in December 2019."