Why are there green lights in tunnels?
Why are there green lights in tunnels? These green bands will move at a speed safe and appropriate to traffic conditions in the tunnel with hopes to encourage drivers to maintain a consistent speed, while never exceeding the tunnel's speed limit of 80 kilometres per hour.
What is the longest tunnel on earth?
The Laerdal Tunnel in western Norway is the longest road tunnel in the world. It takes about 20 minutes to pass through the tunnel. Brightly colored lights placed every six kilometers help drivers stay alert.