World’s Longest Road Tunnel: Laerdal – Aurland

Europe Norway Facts - Worlds longest tunnel, the laerdal tunnel, outside
Europe Norway Facts - Worlds longest tunnel, the laerdal tunnel, outside

Author: Arne Brekke, Brekke Tours.

It was a privilege to be present when the King of Norway cut the ribbon for the opening of the world’s longest road tunnel between Lærdal and Aurland on November 27, 2000. Several thousand persons attended this historic event in beautiful fall weather. Prior to the ribbon-cutting ceremony, the musician Karl Seglem played his own especially composed music on a bukkehorn, or ram’s horn, to entice the “trolls” (children from Årdal, Lærdal and Flaam, dressed in red, green and yellow outfits with tails) out of the mountain to salute His Majesty. King Harald and his entourage were the first to pass through the tunnel, and they were met in Aurland and Flaam by cheering crowds carrying Norwegian flags. Lunch was served at the new Fretheim Hotel.

The Lærdal Tunnel was built during a five-year period from 1995-2000 at a cost of approximately 125 million U.S. dollars. It is an important link in the ferry-free road connection between the Bergen area and Eastern Norway, including Oslo, and is especially significant for winter traffic, when the high mountain passes are closed, or subject to closing, because of snow. The mountains above the tunnel reach elevations up to 1809 meters (5935 feet), and the breathtaking high-mountain road between Aurland and Lærdal, the so-called Snow Road, is open only for a few months during the summer. This tunnel is not only the world’s longest, 24.5 km ( 15.2 miles), but also the world’s most uniquely constructed tunnel with exceptional security features. (The world’s second longest, the St. Gottard Tunnel in Switzerland, is only 16.92 km, or 10 miles). An access tunnel of 2.1 km (1.3 miles) was built from a side valley, Tynjadalen (Tønjum Valley), 6 km (3.72 miles) from the Lærdal side. This enabled the crews to drill from four sites, which shortened the construction time. This access tunnel also serves as an extraction tunnel for the ventilation system, and made it possible to deposit the excavated rock on the Lærdal side in an environmentally secure area.

High air quality in the tunnel is achieved in two ways, by ventilation and purification. Large fans draw air in from 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 100-meter (328 feet) cavern 9.5 km (5.9 miles) from Aurland, that removes both dust and nitrogen dioxide from the tunnel air. Two large fans draw air through the treatment plant, where dust and soot are removed by an electrostatic filter. Then the air is drawn through a large carbon filter which removes the nitrogen dioxide.

To support and strengthen the ceiling and the walls of the tunnel, 200,000 steel bolts of up to 5 meters (16 feet) in length have been used, and 35,000 square meters (42,000 square yards) of concrete has been poured!

The new tunnel is of great importance to Aurland, not only for its connection eastward, but also for greatly improved contact to its own district, especially Lærdal, Årdal, Sogndal, Luster, Leikanger and Balestrand, as well as Sunnfjord and Nordfjord. Inner Sogn, previously isolated by high mountains, has suddenly become the navel (navle: central point) of Norway, to quote the newspaper Bergens Tidende.

In order to break the monotony of a 20-minute drive, the tunnel has been divided up into four sections by creating three large caverns, or mountain halls, 6 km (3.7 miles) from each end and one in the middle. Special attention has been paid to the lighting. Whereas white light is used in the tunnel itself, the mountain halls are equipped with blue and yellow light. This gives one the illusion of driving into daylight every 6 km (3.7 miles), and the golden light along the floor gives the illusion of sunrise! To keep the drivers from being inattentive or falling asleep, and thus causing head-on collisions, each lane is supplied with a loud rumble strip toward the center!

Thousands of tourists drive through the tunnel for the unique experience. A romantic ambiance has even been suggested when a couple decided to get married in one of the mountain halls ! A group of women from Årdal, Lærdal and Aurland, calling themselves jenteslepp “gals’ night out”, have had an organizational meeting in the tunnel!

The following are some of the exceptional security measures taken in case of accidents and/or fire:

– Emergency phones marked SOS have been placed every 250 meters (820 feet)
– Fire extinguishers have been placed every 125 meters (410 feet), which is closer than in other tunnels
– Stop lights and signs reading: snu og køyr ut, “turn and drive out”, go on when one of the emergency phones is used
– 15 turning areas have been constructed for buses and semi-trailers
– In addition to the three mountain halls, emergency niches have been built every 500 meters (1640 feet)
– Emergency phone channels for police, fire departments and hospitals
– Data connections to night-watch and security centers in Lærdal and Bergen
– Special wiring for the use of radio and mobile phones
– Photo inspection and counting of all vehicles entering and exiting the tunnel

A total of 2.5 million cubic meters (3.27 million cubic yards) of rock has been removed from the entire tunnel. On the Aurland side, the excavated rock has been used for various municipal purposes, to build part of the new highway between Flåm and Aurland , and for a unique pedestrian and bicycle path along the Aurland Fjord from Flåm to Otternes. In order to gain the necessary width for the path, large quantities of rocks were dumped in the fjord. With landscaping, blacktopping, and wooden railings, this is probably the most exquisite and expensive path in the world!

The Lærdal Tunnel is rapidly receiving world attention. Early in December, “Time Magazine”, with world-wide circulation, carried an excellent photo and text. The Aurland/Lærdal Tourist Office has received numerous inquiries from the United States, South America and Japan, and other countries. They were amused, however, when a lady from Minneapolis sent them a letter thinking that the new tunnel was being constructed from Oslo to Bergen, a distance of 287 miles! She expressed the hope that one could still get out at Myrdal to visit the Flåm Valley, Aurland and Voss!

Written January 21st, 2001.

Location: Aurland, Fjord Norway.