ABSTRACT

The Zimmerberg Base Tunnel a project of the Swiss Federal Railways represents the longest doubletrack tunnel under construction for over 100 years. The Zimmerberg Base Tunnel Part 1, Zurich Central Railway Station – Thalwil, is a core project of the Swiss Federal Railway (SBB) Bahn 2000 project. Part 1 provides a rapid, effective corridor towards the east of Switzerland and the Grisons. The planned extension, Part 2, will increase capacity towards the south, making the Zimmerberg Base Tunnel part of the Germany – Basel – Zurich – Gotthard -Italy axis. The double-track tunnel is designed for speeds in excess of 200 km/h. The investment costs of this 10.7 km section amount to CHF 820 m. The construction work was started in September 1997, and the opening is planned for June 2003.