The tunnel was designed to be claustrophobia-friendly by using lighting and wider sections to break the visual monotony.
Each of the three caverns is carved out of the mountain to create a 'mountain hall' effect with unique light installations.
An air treatment plant at the Aurland end was the first of its kind in the world for a road tunnel.
The project involved the removal of approximately 2.5 million cubic meters of rock.
Automated incident detection systems monitor traffic flow to ensure safety throughout the long drive.
Despite the length, the speed limit is 80 km/h throughout the tunnel.
The mountain cover above the tunnel reaches depths that exceed those found in many other major Alpine tunnels.
Lærdalstunnelen is a 24.5-kilometer-long road tunnel in Norway, currently holding the record as the world's longest road tunnel. It connects the municipalities of Lærdal and Aurland, providing a ferry-free connection between Oslo and Bergen. The engineering design incorporates three large mountain caverns situated at six-kilometer intervals to break the monotony for drivers and provide emergency turnaround points. These caverns are illuminated with blue and yellow lighting to simulate sunrise and prevent driver fatigue. The tunnel ventilation system utilizes a specialized air treatment plant located near Aurland to remove nitrogen dioxide and dust from the air. Construction began in 1995 and was officially opened to traffic in 2000. It is a vital segment of the E16 highway. The tunnel reaches a maximum depth of 1,400 meters below the mountain surface.
The interior of the illuminated mountain caverns, where the lighting design is specifically intended to be visually distinct.
Check your fuel level before entering, as there are no gas stations inside the tunnel.
Maintain the recommended distance from other vehicles and stay alert, as the tunnel's length can induce drowsiness.
Use the mountain caverns as a brief resting point if you feel tired; they are safely designated areas for stopping.
Do not stop or park outside of the designated mountain caverns, as stopping in the main tunnel lanes is dangerous and prohibited.
Open year-round, though temporary closures for maintenance may occur during overnight hours.
Keep your headlights on at all times and follow the posted speed limits strictly.
