The Lærdal Tunnel () is a  road tunnel connecting the municipalities of Lærdal and Aurland in Vestland county, Norway, and located approximately  northeast of Bergen. The tunnel carries two lanes of European Route E16, and was the final link completing the main highway that now enables car travel between Oslo and Bergen with no ferry connections and no difficult mountain crossings during winter. It is the longest road tunnel in the world, succeeding the Swiss Gotthard Road Tunnel.

In 1975, the Parliament of Norway decided that the main road between Oslo and Bergen would run via Filefjell. In 1992, Parliament confirmed that decision, added that the road should run through a tunnel between Lærdal and Aurland, and passed legislation to build the tunnel. Construction started in 1995 and the tunnel opened in 2000. It cost 1.082 billion Norwegian krone ($113.1M USD).

Beginning in 2025 and for around four years, the tunnel will be completely closed for fourteen hours each night for upgrades to meet recent changes to EU safety regulations. Alternative routes such as road 50 are available, but are slower and often closed in winter.

Design
A total of  of rock was removed from the tunnel during its construction from 1995 to 2000.  The tunnel begins just east of Aurlandsvangen in Aurland, goes under a mountain range, and ends  south of Lærdalsøyri in Lærdal. Its design takes into consideration the mental strain of driving through a long tunnel; it is divided into four sections, separated by three large mountain caves at  intervals.  While the main tunnel has white lights, the caves have blue lighting with yellow lights at the fringes to give an impression of sunrise. These caves are meant to break the monotony, providing a refreshing view and allowing drivers some relief. They are also used as turnaround points, and as break areas to help alleviate claustrophobia during the 20-minute drive through the tunnel. In the tunnel, there are signs every kilometer indicating how many kilometers have already been covered and how many still to go. To alert drivers who become inattentive or start to fall asleep, each lane is supplied with a loud rumble strip towards the centre.

Safety
The tunnel does not have emergency exits. There are many safety precautions in case of accidents or fire. Emergency phones marked "SOS" are installed every  for contacting the police, fire departments, and hospitals.  Fire extinguishers are placed every .  Whenever an emergency phone in the tunnel is used or a fire extinguisher is lifted, stop lights and electronic signs reading  (English: turn and exit) are displayed throughout the tunnel, and electronic signs at the entrance show  (English: Tunnel closed). There are fifteen turnaround areas which were constructed for buses and semi-trailers. In addition to the three large caverns, emergency niches have been built every . There are photo inspections, and a count is kept of all vehicles entering and exiting the tunnel at security centres in Lærdal and Bergen. There is also special wiring in the tunnel to enable the use of radio and mobile phones. Speed cameras have been installed  because of serious speeding. There are very few other completely straight roads in the region.

Air quality
High air quality in the tunnel is achieved in two ways: ventilation and purification. Large fans draw fresh air in through both entrances, and polluted air is expelled through the ventilation tunnel to Tynjadalen. The Lærdal Tunnel is the first in the world to be equipped with an air treatment plant, located in a -wide cavern about  northwest of Aurlandsvangen. The plant removes both particulates and nitrogen dioxide; air is drawn into the treatment plant by two large fans, dust and soot are removed by an electrostatic filter, and then nitrogen dioxide is removed by a large carbon filter.

Media gallery

References

External links

World's longest Tunnel Page

Aurland
Lærdal
Road tunnels in Vestland
2000 establishments in Norway
Tunnels completed in 2000
European route E16 in Norway