Incredibly Engineered Tunnels at Sea!
From submerged passageways that are suspended and float to those that replicate a journey to the Earth’s core, here are 13 Incredibly Engineered Tunnels at Sea!
1. Transbay Tube
The Transbay Tube is a 5.8-kilometer tunnel that carries four trans-bay lines under California’s San Francisco Bay between the cities of San Francisco and Oakland. The tunnel features a maximum depth of 41 meters below sea level and is a monumental time-saver to the cities fighting traffic.
2. The Windsor Tunnel
The second busiest crossing between the United States and Canada, the Detroit-Windsor Tunnel is a highway tunnel connection Detroit, Michigan in the United States with Windsor, Ontario, in Canada.
3. Busan- Geoje Fixed Link
South Korea’s first endeavor in underwater transportation comprises of a tunnel and two bridges fusing an 8.2-kilometer link between Geoje Island and Busan. The undersea tunnel itself is 4 kilometers long.
4. Severn Tunnel
Upon completion of the Severn Tunnel running under the Severn Estuary between England and Wales, the passageway was regarded as a crowning achievement of the times. Running 3.62 kilometers under the water, this marvel is one of the oldest underwater tunnels in the world, having been built between 1873 and 1886.
5. The Channel Tunnel
According to masters of engineering, the Channel Tunnel— an architectural wonder spanning 50 kilometers— is the best underwater tunnel in the world. When contemplation for an undersea passageway is in the works, it has been said that a nation will look to the engineering of the Channel Tunnel for inspiration.
6. Tokyo Bay Aqua-Line
This next advancement in engineering is considered the fourth-longest underwater tunnel in the world. Also called the Trans-Tokyo Bay Highway, the Tokyo Bay Aqua-Line connects Japan’s city of Kawasaki with the city of Kisarazu. With an overall length of 14 kilometers, it includes a 4.4-kilometer bridge as well as a 9.6-kilometer tunnel that runs beneath the bay.
7. Marmaray Tunnel
Running 76.6 kilometers long, workers spent painstaking hours in the depths of the earth’s mantle where alarming discoveries were made. Relics from the Byzantine-era along with countless other 8,000-year-old finds were recovered from the site of the European tunnel terminal in 2005.
8. Bund Sightseeing Tunnel
While some may deem Shanghai’s underwater Chinese tunnel short and sweet— slightly strange and spectacular may better fit the description. The Bund Sightseeing Tunnel spans the Huangpu River and connects Shanghai’s Bund to Lujiazui.
9. SMART Tunnel
Smart and innovative for the win— in Kuala Lumpur, Malaysia, engineers put their heads together to create the first combined road and flood relief tunnel. Here, the longest tunnel in Malaysia can get completely flooded and turned back into a road in just a few hours.
10. The Øresund Bridge
Merely by looking at the structure one can grasp the mastery that went into the Oresund Bridge— a combined railway and motorway bridge across the Oresund strait between Sweden and Denmark. The cabled-stayed structure runs 8 kilometers from the Swedish coast to Peberholm.
11. Seikan Tunnel
Spanning a total length of 53.8 kilometers with 23.3 of those kilometers under the ocean floor, the anomaly travels beneath the straight to connect Aomori Prefecture on Honshu Island with Hokkaido Island. Also known as Seikan Zuido, the tunnel’s concept was birthed in 1940 and construction wasn’t completed until almost 50 years later.
12. Gotthard Base Tunnel
After 20 grueling years of construction, the Gotthard Base Tunnel was completed in 2016 and swiftly stole the title from the Seikan in Japan as the world’s longest tunnel. The deepest-ever constructed, this submerged passageway runs 57.5 kilometers under the snow-capped Swiss Alps. 8,000 feet deep at its max, the tunnel required 31 million tons of displaced rock.
13. Floating Tunnels of Norway
Taking 7 ferries along the way, the 700-mile trip between the cities of Kristiansand in the south and Trondheim in the north will typically run someone 21 grueling hours. But soon, the Norwegian government proposes a 40-billion-dollar infrastructure project which aims to replace ferries with bridges, conventional tunnels, and what may become the world’s first floating tunnel.
