Norway is constructing “Rogfast,” a massive road tunnel set to become the world’s longest and deepest undersea road link. Spanning 27 kilometers (17 miles) and reaching a maximum depth of 392 meters (1,286 feet) below sea level, the dual-tube tunnel is a crucial part of the E39 coastal highway revamp, aiming to create a ferry-free route along the nation’s western coast.
Slated for completion in 2033 at a cost of approximately $2.4 billion. Rogfast will drastically cut travel time, reducing the journey between Bergen and Stavanger by about 40 minutes, and significantly improve connectivity for the Stavanger and Haugesund regions.
🚨Breaking: Norway is building the world’s longest and deepest undersea road tunnel. The Rogfast tunnel will stretch 26.7 km and reach 390–392 m below sea level, connecting key coastal cities and reducing reliance on ferries.
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Building the tunnel poses immense technological challenges, including extensive saltwater leakage, requiring sophisticated grouting methods to seal the rock as crews drill deeper. To ensure the two ends meet with a strict precision of just 5 centimeters (1.97 inches), contractors are using high-tech laser scanners and “digital twin” mapping.
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A unique feature of the design is a double roundabout built 260 meters deep roughly halfway through, providing a connection tunnel to the island municipality of Kvitsøy. While the project is technically demanding, it is expected to have positive long-term effects on the local economy, logistics, and regional development by boosting access to jobs and services. The tunnel will use a longitudinal ventilation system complemented by shaft ventilation to ensure motorist safety and clean air.
