Quality brings great things to light

Tunnel construction

Implenia Tunnelling in figures


Number of countries


Tunnelling kilometres


Reference projects

Our services

Transport tunnels

More information on service tunnels

Further information on power plant construction


Tunnelling and its importance


A selection of our best projects

Semmering Base Tunnel SBT Lot 2.1

The planned Semmering Base Tunnel (SBT) is currently one of the most important large-scale infrastructure projects in the heart of Europe and part of the new Austrian Southern Railway, which is the central axis on the trans-European route from the Baltic Sea to the Adriatic Sea.

Read more


The new Wendlingen-Ulm line (NBS), together with Stuttgart 21, significantly improves Baden-Württemberg's infrastructure and thus creates shorter travel and transport times not only in Baden-Württemberg but also across Germany and Europe.

Read more

Lyon Metro Line B

This project, with a length of approximately 2.5 km, will extend line B from Gare d'Oullins station to Hôpitaux Lyon Sud station and create two additional stations. The journey time between Oullins station and the Lyon Sud hospitals is 3 minutes and 20 seconds.

Read more

Nant de Drance pumped storage power station

The project involves the construction of a pumped storage power plant between the two dams Emosson and Vieux Emosson. The new power plant cavern is located at approx. 1700 m a.s.l. Access to the underground facility is from below through a 5 km long tunnel and from above through a 2 km long tunnel system.

Read more

Slussen SN91

Extensive rock and concrete work at Katarina Mountain. To accommodate Stockholm's continuous development, Slussen is rebuilt and a bus terminal is built at Katarinaberget.

Read more
Sandbukta-Moss-Såstad (SMS2A)
Sandbukta-Moss-Såstad (SMS2A)

Sandbukta-Moss-Såstad (SMS2A)

The new double-track project Sandbukta-Moss-Såstad (SMS2A) is part of the Intercity development and one of the plots in the connection to Halden (west line of Østfoldbanen). On the line, 10.3 km of double-track will be rebuilt, partly in tunnel and partly in daytime.

Read more


Here is a selection of our tunnelling news