Longest and deepest undersea tunnel is now being built

“Norway is currently building a 26.7-kilometer-long subsea road tunnel, which will be the longest and deepest in the world once completed,” reports The Doomslayer.

MIT Technology Review explains:

I’m in this odd situation under the iconic fjords of Norway to visit what will soon become the world’s longest and deepest subsea road tunnel, called Rogfast. I want to understand how you make something as audacious as a 26.7-kilometer (16.6-mile) highway that sits 390 meters (1,280 feet) below the sea at its deepest point…

The Norwegians already have the world’s longest subsea tunnel, the 14.4-kilometer Ryfylke, though Rogfast will dwarf it. Their expertise has attracted attention from Japan, Spain, Morocco, and even a number of US states, whose representatives were due to visit the site in May…

The entire endeavor feels like an obstinate refusal to give in to physics and geology… There’s not just the blasting of the tunnel itself—although that is an epic project on its own—but an immense logistics challenge involving huge ventilation shafts, extreme pressure, underground roundabouts, and the complex Norwegian geology…

After it’s completed, which is scheduled to happen in 2033, Rogfast should help eliminate two ferry routes and cut the five-hour journey between the southwestern cities of Stavanger and Bergen by 40 minutes. It will funnel four lanes of traffic deep beneath the fjords of Boknafjord and Kvitsøyfjord, and at one section a relatively scant 50 meters of rock will separate the drivers speeding through the tunnel from the bottom of the North Sea. There are also, delightfully, two undersea roundabouts located 220 meters below sea level.

A vast undersea tunnel is also being built in the Baltic Sea south of Denmark, but that tunnel is only 11.2 miles long, not quite as long as the 16.6 mile tunnel being built in Norway.

The tunnel between Denmark and Germany will make it much faster to travel from Zealand — the largest and most populous island of Denmark — to Germany, Right now, travelers from Denmark’s capital Copenhagen (which is located on Zealand) first have to drive west to Jutland, before traveling south to Germany. This tunnel will allow them to take a much more direct route south to Germany, going by tunnel from the Danish city of Rodbyhavn to the German city of Puttgarden.

That tunnel will also make it quicker for German motorists to drive to Sweden and Norway.