The Kerenzerberg Tunnel: Tunnel On The A3 Motorway

The article discusses the Kerenzerberg Tunnel, a significant engineering achievement in Switzerland that connects the towns of Niederurnen and Mühlehorn. This unidirectional tunnel, part of the A3 motorway, serves as a vital transportation link between Zurich and the scenic Lake Walen region. Stretching 5,760 meters, the tunnel offers captivating views of the Swiss Alps along its route.

The tunnel lies south west of Wallensee, a large lake in east Switzerland. It forms part of the A3, which is the main route from Basel and Zurich to Sargans.


The Kerenzer Tunnel

The unidirectional tunnel, a vital artery in eastern Switzerland, cuts through the imposing Kerenzerberg mountain ridge, linking the towns of Niederurnen and Mühlehorn. Situated in the canton of Glarus, it forms a pivotal segment of the A3 motorway, a crucial route that connects the urban hub of Zurich with the picturesque shores of Lake Walen. Nestled in the heart of the Swiss Alps, this tunnel facilitates travel between Glarus and St. Gallen. . Mesmerizing views of the surrounding peaks and valleys are enjoyed on either side of this 3.6-kilometre tunnel. It is easily reached via different toll routes, with live news available online. At present, there is no webcam available showing tunnel conditions.

Kerenzerberg Tunnel - Toll Free

There are no direct fees payable to pass through the tunnel. However, some of the approach routes are part of the national toll road system, so it is the driver's interest to purchase a Swiss vignette to ensure efficient travel. Furthermore, to traverse the tunnel on the A3 from Basel to Sargans, a Swiss Motorway vignette is not an option, but a requirement, ensuring adherence to Swiss road regulations.

Elevation and Length

Travelling only in one direction, with reverse traffic passing roughly parallel, through six former railway tunnels along the banks of the Walensee.

Length 5 760 m (18,900 ft)
Elevation 420-440 m
Number of Tubes 1
Lanes 2 (One way only)
Travel Time * 4.5 minutes

*Travel time is a rough guide only and may depend on congestion levels and weather conditions in the surrounding area.

Terms of Use & Restrictions

Here is an overview of the rules and regulations applicable to drivers using the tunnel:

  • Drivers must follow the rules applicable to all who use the Swiss road network. This includes all restrictions applicable to individual drivers, vehicle loads and classes.
  • Speed limit - 80 km/h (50 mph).
  • Drivers should be aware of the inherent risks of driving in tunnels. Every vehicle should carry an emergency hazard triangle to deploy in the event of a breakdown or accident.
  • Vehicles may not transport dangerous goods through the tunnel.


  • Ambulance: 144
  • Police: 117
  • Firefighters: 118
  • Universal European emergency number: 112
  • Swiss traffic information service (TCS) - +41 800 140 140

You can request Roadside Assistance in Switzerland using the following numbers:

  • Emergency Call / Vehicle Breakdown Serivce: 140
  • TCS Touring Club Switzerland - Toll free number: 0800 808 114
  • TCS Touring Club Switzerland - International number: +41 58 8276316

Kerenzerberg Tunnel Current & Live Webcam

  • The tunnel is open 24 hours a day, 7 days a week. For the most up-to-date news regarding the tunnel, you can view the official website for the tunnel.
  • You can check Kerenzerberg Tunnel Weather here.
  • There is no webcam for the tunnel

Are there alternative routes to the Kerenzerberg Tunnel?

 An alternative route along Route 3, which runs to the south of the tunnel route. However, it is important to note that this route is significantly longer. Deciding which route to take will also be determined by the intended destination. Always remember the role that the weather may play when choosing your route.

Kerenzerberg Tunnel FAQ:


The tunnel has a length of 5,760 metres (18,900 ft). It forms part of the A3 motorway from Basel and Zurich to Sargans.
It is a one-way tunnel, carrying vehicles from Zurich to Sargans, whilst traffic from the opposite direction runs through re-purposed short tunnels originally built for the railway. The route runs roughly parallel.
Opposing traffic runs along the shores of the Walensee through six short tunnels originally built for a railway, indicating an integrated transportation strategy with nearby infrastructure.
A safety upgrade, including a parallel safety gallery is underway. It serves as an escape route and exhaust duct, improving safety protocols.
Opened in 1986 and without significant maintenance since then, the latest upgrades modernise its safety guidelines and standards.