Norway is building an unprecedented underwater road tunnel, Rogfast, a megaproject that promises to change the way we travel along the country’s west coast and which stands as one of the most ambitious engineering works in Europe.
Rogfast, short for Rogaland Fixed Link, is an underwater road tunnel under construction under the Boknafjord and Kvitsøyfjord fjords in the Rogaland region. When completed, it will connect by road the municipalities of Randaberg, next to Stavanger, and Bokn, with a branch to the island of Kvitsøy, creating a continuous connection on the European highway E39 along the Norwegian Atlantic coast.
With around 26.7 kilometers long and a maximum depth of close to 390 meters below sea level, Rogfast is expected to become the longest and deepest underwater road tunnel in the world, surpassing the current record holder, the Lærdal tunnel. If the schedule is met, the opening to traffic remains scheduled for 2033, according to information provided by the international news channel Euronews.
With an estimated budget of around 25 billion Norwegian kroner, approximately 2 billion euros, the tunnel is expected to have a significant impact on the local economy, especially in the transport, tourism and industrial sectors.
A megaproject that transforms the E39
Rogfast is part of the Norwegian program to make the E39 a “ferry-free” route, connecting large cities such as Kristiansand, Stavanger, Haugesund, Bergen and, further north, Trondheim. Currently, this route continues to depend on several sea crossings, which make journeys longer and more vulnerable to weather conditions.
By eliminating the ferry between Mortavika and Arsvågen, the new tunnel is expected to reduce travel time between Stavanger and Bergen by around 40 minutes, facilitating daily commutes for workers and making freight transport more predictable.
In conjunction with other projects already underway on the E39, studies continue to point to significant reductions in total travel time along the west coast, according to the same source.
Record length and extreme depth
Rogfast’s main tunnel will have two parallel tubes, each with two lanes, connected by transverse galleries that function as evacuation routes in case of emergency.
The maximum depth, close to 392 meters below the sea surface, requires the use of specific technical solutions for ventilation, drainage and fire protection, designed to guarantee a minimum useful life of one hundred years.
In addition to the main gallery, the project includes the Kvitsøy tunnel, a branch of approximately 4 kilometers that will allow a permanent road connection to the island of Kvitsøy, the smallest municipality in Norway, currently dependent on ferry connections.
Kvitsøy and the roundabouts at a depth of 260 meters
One of the most unique features of Rogfast is the junction to Kvitsøy, designed with two roundabouts excavated inside the rock, around 260 meters deep, according to the same source.
This solution allows traffic to be distributed between the main tunnel and the island branch in a single transversal section, something uncommon in infrastructures of this type.
According to those responsible for the project, this configuration also offers operational advantages. In the event of a serious accident in one of the tubes, it will be possible to partially close the tunnel and divert traffic to the parallel tube, maintaining circulation in both directions through the roundabouts and internal ramps.
Security and technology inside the tunnel
According to previously released information, the Rogfast design continues to prioritize road safety. The project envisages two separate tubes, evacuation passages at regular intervals, ventilation systems prepared for fires involving heavy vehicles and an extensive network of cameras and sensors for continuous traffic monitoring.
Drivers will be guided by dynamic signage and, in emergency situations, will be able to use properly marked exits to access the parallel tube, facilitating the intervention of rescue teams. The Norwegian authorities continue, according to the same source, to point to this model as a reference for large road tunnels.
The size of the technological component remains impressive. The electrical contract, awarded in recent years, involves the installation of more than 1.3 million meters of cables, hundreds of emergency telephones, thousands of lane signs and a video surveillance system with more than a thousand cameras along the entire route. Installation work is scheduled to take place between 2028 and 2032.
Where are the works going this year?
Construction of the underwater tunnel began in 2018, having been temporarily suspended in 2019 due to budget overruns and the need to review contracts and financing. After a new decision by the Norwegian parliament in 2020, works resumed in full in 2021, with a phased model of major works.
In 2025 and early 2026, the Norwegian road administration continues to underline the “good progress” of the three main excavation contracts, according to .
More than ten kilometers of the route have already been excavated and, under Kvitsøy, the first underwater roundabout has been completed. In parallel, work continues to open the ventilation shafts, approximately 220 meters high, from the island to the interior of the tunnel.
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