You're getting used to using tunnels and driving under the surface on your way from Bergen to Oslo quite quickly. We passed over 70 tunnels in the 8 hours of driving. The longest of these is the Lærdalstunnel, with over 24km in length its the longest road tunnel on earth.
The special thing about this tunnel are the three stopping points that are placed after every quarter. They are lit in bright colours and are - apart from the generally blue light also shining in orange, yellow and green. Maybe even more but those are the three colours we spotted on our way through.
The acoustic is special, too. According to Are its one of the most beautiful but also most unpractical concert halls worldwide because of the terrific acoustics that even come with an echo-effect being drowned by a thundering semi truck just a moment later.