The construction: Basic concept & key figures

Lötschberg base tunnel

Basic concept

The Lötschberg base tunnel is currently the most modern, secure and technically complex rail tunnel in the world.

It was designed with twin single-track tubes to ensure optimum reliability, but for financial reasons, only one of the tubes was fully equipped, while the second was left largely as a shell (see page 46 for possible expansion phases). The two tubes are connected by transverse tunnels at 333-metre intervals, meaning that each main tunnel serves as the evacuation tunnel of the other. All systems are duplicated in the tunnel. This “twin installation” means that operations can continue in the event of any technical problems.

Construction key figures

Base tunnel length 34.6 km
Total of tunnelled tubes and galleries
with cross-passages:

88.1 km
91.8 km
Axial distance between tunnel tubes 40 m
Number of cross-passages between tubes 104
Elevation at Frutigen north portal 776.5 m..M.
Elevation at highest point 828.2 m..M.
Elevation at Raron south portal 654.2 m..M.
Min. gradient 3
Max. gradient 13
Total of excavated material
Entspricht Anzahl Lastwagen
16.6 Mio. tonnes
(= approx. 830,000 lorry loads)
Investment volume CHF 4'300 Mio.


Further information:

» Basic concept & key figures

» The railway tunnel

» Other tunnel sections

» Systems and functions

Tunnel sections:

Tunnel areas