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A tunnel unlike anything built before: Norway's Rogfast will be the world's longest and deepest subsea road tunnel — 26.7 kilometers, plunging 390 meters beneath the North Sea — built entirely by blowing up rock, one blast at a time.

Water is the enemy you can never fully defeat: The crushing pressure of the sea above means water always finds a way in; engineers constantly drill ahead, test for leaks, and pump cement-like grout into the rock just to stay ahead of the ocean.

The dangers are stranger than you'd expect: Beyond explosions and flooding, designers worry the 30-minute drive will literally put motorists to sleep — so artists will be commissioned to fill the tunnel with shifting lights and colors to keep drivers conscious.

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Jul 10, 2026 — longest and deepest subsea road tunnel, called Rogfast … a 26.7-kilometer (16.6-mile) highway that sits 390 meters (1,280 feet) below the sea ...

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The world's longest subsea road tunnel | Spectacular Norway

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4 days ago

Norway is Building The World's Deepest Mega-Tunnel

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Jun 3, 2026

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How the World's Deepest Undersea Mega Tunnel Is Being Built

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The worlds longest subsea road tunnel | Spectacular Norway

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820 Feet Below the Sea, Norway Has Finished the World’s First Underwater Tunnel Roundabouts Norway is pushing engineering to new depths with Rogfast, a 16.6-mile undersea highway tunnel that will become the world’s longest and deepest road tunnel

2.2K+ reactions · 1 day ago

DeepInScience721

Facebook

1:02

The world’s deepest underwater road tunnel is being built in Norway. 🌍 Nearly 400 meters below the ocean, drivers will travel through a 27 km tunnel featuring one of the world’s most unique underground highway interchanges. The future of infrastructure is already here. 🚗🌊 #norway #megaproject #geopolitics #worldfacts

1.3K+ likes · 2 weeks ago

realgeolol

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0:16

Some of the world's most impressive roads aren't built over mountains... They're built beneath the sea. Norway's Rogfast project is redefining what modern infrastructure can achieve. Stretching nearly 27 kilometers beneath a fjord, it will become the world's lon

120+ reactions · 1 month ago

Vadim Matskovyak

0:37

The world’s longest subsea road tunnel 🤩🇳🇴

520+ reactions · 3 days ago

spectacularnorway · Facebook

Film production company

The 16 mile Rogfast underwater tunnel in Norway. When it opens in the early 2030s, Norway’s Rogfast will claim the title of the world’s longest and deepest subsea road tunnel. Its real distinction, however, lies in how it solves problems no ordinary underwater road has ever faced at this scale. A plunge into the bedrock The tunnel stretches 26.7 kilometers (16.6 miles) and drops to 392 meters (1,286 feet) beneath the Boknafjord. Rail tunnels can be longer because trains run on predictable schedules in controlled environments. Road tunnels must continuously manage vehicle exhaust, provide emergency access, and keep drivers safe inside a sealed tube. The fjord’s steep underwater slopes leave little choice: the only way to maintain a thick, stable ceiling of solid rock above the roadway is to drive the entire route deep into the bedrock itself. A hidden junction beneath the waves Roughly midway, the main twin-tube tunnel meets a 3.7-kilometer spur that spirals upward throug

May 31, 2026

BrianRoemmele · X

AI & neural networks professional

1:51

The B1M. . Construction projects don't get more ambitious than this. See how Norway is building the world's longest and deepest undersea road tunnel in our epic full documentary, produced in partnership with Procore Technologies - link in the comments 🏗️

7.8K+ reactions · Jun 3, 2026

TheB1M · Facebook

Construction video channel

Norway is building a record-breaking road tunnel nearly 400 metres beneath the sea. 🚗🇳🇴 The 26.7-kilometre Rogfast tunnel is being constructed beneath the Boknafjord, connecting Randaberg and Bokn in western Norway. When completed, it will become t

1.7K+ reactions · 2 weeks ago

KnowledgeFactoryIndia

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Norway is drilling a road 1,280 feet beneath the ocean floor and it may be the most ambitious engineering project on Earth right now. 🌊 The Rogfast tunnel, stretching 17 miles through solid bedrock beneath Norway's western fjords, will become the world's lon

60+ reactions · Jun 4, 2026

Neil deGrasse Tyson · Facebook

American astrophysicist and writer

0:17

Driving through the Ryfast Tunnel is always an unforgettable experience - colorful lighting and the feeling of traveling deep beneath the sea 🇳🇴 It’s not just a tunnel, but a true engineering wonder. Ryfast is part of the world’s longest undersea road tunnel syste

610+ reactions · May 8, 2026

crazytroll.no

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For most people, a tunnel is something built through a mountain or under a river. But engineers in Norway are exploring something that sounds almost impossible: a road tunnel that floats underwater. Norway has one of the longest and most rugged coastlines

50+ reactions · Jun 4, 2026

Physics Is Fun

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Ryfylke Tunnel

Wikipedia

https://en.wikipedia.org › wiki › Ryfylke_Tunnel

It is 14.4 kilometres (9 mi) long [2] and is currently the world's longest subsea road tunnel, and the deepest tunnel of any kind.

Inside the world's deepest and longest subsea road tunnel

Spotify

https://open.spotify.com › episode

Norway's Rogfast is an exceptional engineering feat, opening a route for drivers deep below the North Sea. This story was written by Niall Firth and ...Read more

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