• The H4 section between the Nanos interchange and Vipava, heading towards Nova Gorica, is expected to be closed until mid-November 2025 due to work on wind protection measures, structures and carriageway resurfacing and reconstruction.
• A detour for local traffic is available via the regional road from Razdrto towards Vipava. At the Vipava junction, drivers can rejoin the H4 (applies to all passenger vehicles, buses and local goods traffic with a destination in Slovenia).
• All transit goods traffic weighing over 3.5 tonnes heading towards Italy is being diverted via the Fernetiči border crossing.
• Traffic is flowing smoothly in both lanes of the H4 from Vipava towards Razdrto, with no diversions.
H4, THE NANOS–VRTOJBA EXPRESSWAY
The section of the Vipava expressway between the Nanos interchange and the Vipava junction, through Rebrnice, is one of the most dangerous sections for traffic management due to the extremely unfavourable weather conditions, which include strong winds (the bora) requiring traffic restrictions for certain vehicle types.
This section is also difficult due to the road gradient (at 6%), it has no emergency lanes, and it is close to Goli vrh, which is the highest point on the motorway in Slovenia and is linked to snow conditions and poor visibility.
In addition, goods traffic has increased substantially.
TRAFFIC CONDITIONS FROM THE END OF SUMMER 2025
CLOSURES AND TRAFFIC ARRANGEMENTS
From mid-August to the end of November 2025, the carriageway between Razdrto and Vipava towards Nova Gorica will be completely closed for 100 days.
Traffic will be organised as follows during this period:
• Passenger vehicles, buses and local goods traffic with a destination in Slovenia will be diverted from the A1 motorway (Ljubljana–Koper) to the regional road between the Razdrto and Vipava junctions, where they will rejoin the expressway.
• Transit goods traffic towards the Vrtojba border crossing will be diverted to the A3 Kras motorway and the Fernetiči border crossing.
• All traffic from Nova Gorica towards Razdrto (Ljubljana/Koper) will be diverted to the expressway, using both lanes. From mid-October to the end of November 2025, traffic will be diverted onto the opposite carriageway for a distance of just under 6 km.
From December 2025 to mid-January 2026, the overtaking lanes on both carriageways will be closed on the low-lying section of the expressway (between the Mlake shooting range and the Vipava junction).
In mid-November 2024, extensive work began on the H4 Nanos–Vipava–Ajdovščina expressway.
The works will be carried out in different phases until the end of 2026 and will include sections between Razdrto, Vipava, Ajdovščina and the Vipavski Križ cut-and-cover.
DARS is carrying out extensive reconstruction work on the H4 Razdrto–Vipava–Ajdovščina expressway–Vipavski Križ cut-and-cover, which will include:
• Additional wind barrier placement
• Carriageway resurfacing or reconstruction
• Additional pile wall construction
• Relocation of the Rebrnica viaduct supports to the base location
Additional closures in the winter of 2025 and in 2026
From mid-January to the end of July 2026, individual carriageways will be completely closed in the low-lying section. During this time, traffic will move in both directions on one half of the expressway. Shorter lane closures of up to 1.5 km will be implemented on the slopes of Nanos to set up wind barriers.
________________________________________
In the final phase, from the end of July to the end of November 2026, the carriageway between Vipava and Nanos, in the direction of Nanos (Ljubljana/Koper), will be completely closed.
Traffic arrangements will be the same as during this year's complete closure:
• Vehicles heading towards Nova Gorica will be diverted to the regional road between the Razdrto and Vipava junctions.
• Transit goods traffic towards the Vrtojba border crossing will be diverted to the A3 motorway towards Fernetiči.
• Traffic from Nova Gorica towards Nanos will be diverted along the reconstructed section of the expressway.
The works on the Razdrto–Vipava section will be carried out in different phases and will be completed by the end of 2026.
This will be followed by work on the Vipava–Ajdovščina–Vipavski Križ cut-and-cover sections.
________________________________________
The traffic arrangement has been adopted with the participation of DARS and the local communities based on the initiative provided by the Municipality of Vipava and the Municipality of Ajdovščina, supported by the Municipality of Postojna.
The Police and emergency services were also of the opinion that two-way traffic on one-half of the expressway through Rebrnice would make interventions and rescue operations difficult in emergency situations. The expressway from Nova Gorica runs along the Nanos slope and rises upwards, which only adds to the risk. This temporary traffic arrangement is an exception due to the construction works and is not planned to be used during other reconstruction works. More.
Source: DARS d.d.
Image: Traffic Information Centre