Lærdal Tunnel

The Lærdal Tunnel in Norway is 24.5 km long and carries the E16 road between Lærdal and Aurland. It opened in 2000 and has three large caves with blue and yellow lighting that give drivers a break from the monotony.

Tunnel lengths are quoted in full road distance. Several longer rail tunnels exist.

Context

The tunnel was built to give the main E16 road between Oslo and Bergen a route that stays open all year. Earlier, the road over the mountains and a ferry crossing were unreliable in winter, and the tunnel replaced them with a single tunnel through the rock between Lærdal and Aurland.

Driving through takes roughly 20 minutes at normal speed limits. Designers worried that such a long, uniform tunnel could make drivers drowsy, so they added three large caverns at intervals, lit in blue and yellow to suggest a sky and a sunrise. The tunnel also has a system to clean and ventilate the air.

Its length of about 24.5 kilometres makes it the longest road tunnel in the world. The next longest road tunnels are well under that length, around 18 kilometres, but the exact figures depend on whether twin tubes and branches are counted. Norwegian road authorities have also planned upgrades to the tunnel's technical equipment, which is routine for a structure of this age.