Flagship Projects

The Swiss Axenstrasse becomes safer

North-south axis: Two new tunnels protect against rockfall

«The new national road along the steep Axen cliffs will result in a win-win situation: firstly, two new tunnels protect the route from rockfalls, and secondly, the village of Sisikon in the canton of Uri is relieved from traffic.»
For centuries, people and goods in Switzerland were transported on the north-south axis via the shipping route. It wasn’t until the construction of the Axenstrasse, connecting the Swiss cantons of Schwyz and Uri, that the path was open for land transport. However, the over 150-year-old connection no longer meets today’s requirements and needs reconstruction. Lombardi is taking on the technical overall management of this ambitious project.

The construction of the new Axenstrasse along National Road N4 is one of Switzerland’s most significant road construction projects. It’s no wonder, as this road is one of the most important routes on the Swiss north-south transit axis, a status it has held for over 150 years.

The new Axenstrasse replaces the existing section of National Road N4 along Lake Uri. The project significantly improves road safety between the central Swiss cantons of Schwyz and Uri. Additionally, the small village of Sisikon, with a population of 380, will be sustainably relieved from traffic.

The centerpiece of this project is the 2,8-kilometer-long Morschacher Tunnel and the 4,4-kilometer-long Sisikoner Tunnel. Both structures will protect the road from external dangers like rockfalls and debris flows. In the past, such natural events have frequently led to the closure of the national road.

Considering that construction work is continuously exposed to the risk of rockfalls for an extended period, an early warning system has been implemented. This system records rainfall, wind and gusts of wind. When predefined limits are exceeded, an SMS warning is sent, leading to the closure of the relevant construction site areas.

A positive side effect on the New Axenstrasse project is that a portion of the excavation material, together with material from the Second Gotthard Road Tunnel, is used for the continuation of the “lakefill” flagship project on the southern shore of Lake Uri. This creates new shallow water zones that provide a habitat for flora and fauna. The “lakefill” project contributes to biodiversity and continues a multi-generational project that began 1985 to enrich the ecosystem of the Reuss Delta sustainably.

  • Conventional and TBM tunnelling
  • Cavern and shaft construction
  • Underground facilities and systems
  • Technical buildings
  • Material Management

The year when the Axenstrasse was established.


The number of vehicles passing through the 380-habitant village of Sisikon on peak days.

Lat: 46.997509
Lng: 8.6242096

Axenstrasse, Sisikon, Uri, Schweiz

20210816 Lowei Nord 006
«The Axenstrasse is a crucial transportation route, not just for Switzerland but also in an international context. With the construction of the Sisikoner and Morschach tunnels, this essential transport artery becomes safer and more reliable in the long term.» Michael Noll