Karawanken Tunnel | New tunnel marks a milestone in European north-south transport

03/24/2026

The new tube of the Karawanken Tunnel has opened after 7.5 years of construction. It strengthens a key north-south link and increases capacity and safety across the European transport network.

On 18 March, the new tube of the Karawanken Tunnel between Austria and Slovenia was officially opened. The approximately eight-kilometre-long border tunnel connects the Karawanken Motorway (A11) south of Villach with the Slovenian motorway network (A2 towards Ljubljana) and forms a key route in European north-south traffic.

Planning and iC services

iC supported the project with geomechanical design, structural calculations for the internal lining, integrated BIM management and comprehensive geotechnical expertise. This included coordination, 3D geological modelling and digital project structuring to ensure a consistent and transparent project workflow.

In addition, ELEA iC introduced innovative approaches, including photogrammetric geological mapping, video scanning, the implementation of a CDE environment, and the use of fibre-reinforced shotcrete in challenging hydrogeological conditions.

Construction under challenging conditions

The construction work took place under challenging geological conditions, particularly on the Slovenian side. On the Austrian section alone, around 1.5 million tonnes of rock were excavated. The water flowing from the mountain – around 600 litres per second – is used in a small hydroelectric power station to supply the tunnel with energy.

Technology and Safety

The new tunnel tube is 7,948 metres long (4,402 metres of which are in Austria) and is equipped with state-of-the-art safety technology. A total of 26 cross-passages to the existing tube, spaced 330 metres apart, ensure safe escape routes. Ventilation, lighting, traffic sensors and video surveillance are all state-of-the-art. In the event of an incident, traffic can be switched to temporary two-way traffic within a few minutes.

Capacity and commissioning

Once fully completed, the capacity of the Karawanken Tunnel will be significantly increased. In particular during the summer months, when up to 30,000 vehicles pass through daily, traffic jams and batch releases are set to be reduced in future. The current toll of €9.00 per car will remain in place.

The new tunnel began operating in phases from 20 March. Since 27 March at the latest, traffic has been running in both directions through the new tunnel whilst the existing westbound tunnel undergoes a complete refurbishment. Full operation with two separate tunnels is scheduled for mid-2029. Until then, the existing bottleneck will remain in place to some extent during peak times.

Project partners and classification

The project was carried out by ASFINAG and the Slovenian motorway operator DARS. The investment amounts to around 340 million euros for the new construction and a total of approximately 570 million euros for the full development, including refurbishment. In addition, the project received funding from the European Union under the Connecting Europe Facility.