Road tunnels represent some of the most remarkable feats of modern engineering, providing vital transport links through mountains, under seas, and across challenging terrains. For automotive manufacturers and drivers alike, these tunnels not only reduce travel times but also demonstrate the ingenuity required to overcome nature’s obstacles.
In this blog, we explore some of the most impressive, record-breaking, engineering marvels, and unique road tunnels from around the globe, highlighting both their technical achievements and the stories behind them.
The Longest Road Tunnel – Lærdal Tunnel, Norway
At an extraordinary 24.5 kilometres in length, the Lærdal Tunnel in Norway holds the title of the world’s longest road tunnel.
This engineering wonder connects Lærdal and Aurland, offering a crucial link through Norway’s mountainous landscape without the need for ferries or winding passes.
Before its completion in 2000, the Gotthard Road Tunnel in Switzerland was often cited as the longest of its kind, but the Lærdal has since claimed the crown.
Designed with driver safety in mind, it features subtle curves, varied lighting schemes, and three large caverns to reduce monotony and maintain concentration during the journey.
The Deepest Underwater Tunnel – Eiksund Tunnel, Norway
Plunging 287 metres below sea level, the Eiksund Tunnel in Norway holds the record for the deepest underwater tunnel in the world.
This submerged route connects several islands to the mainland, transforming local transport and commerce.
Drivers experience a steep descent followed by a lengthy journey beneath the water, demonstrating the extreme capabilities of modern tunnelling techniques.
The Most Dangerous Road Tunnel – Guoliang Tunnel, China
Carved directly into the side of a mountain by local villagers in the 1970s, the Guoliang Tunnel in China is renowned for its perilous nature.
With sheer drops, narrow passages, and minimal safety barriers, it demands caution and respect from drivers.
Its creation is a testament to determination, as it was built by hand over a period of five years to connect the isolated village of Guoliang to the outside world.
Today, it serves as both a functioning road and a tourist attraction for those seeking an adrenaline-filled drive.
The World’s Widest Road Tunnel – Yerba Buena Island, USA
The largest diameter road tunnel in the world can be found beneath Yerba Buena Island in San Francisco, California.
Measuring an impressive 24 metres in width and 17 metres in height, the tunnel accommodates two decks of traffic. Spanning 165 metres in length, it facilitates the passage of more than 280,000 vehicles each day, making it not only a record-holder but also an essential artery in one of America’s busiest metropolitan areas.
Switzerland’s Secret Bunkers – Hidden Protection in the Alps
Switzerland is famous for its extensive network of tunnels, many of which conceal more than just roads.
The nation has a long-standing tradition of incorporating bunkers into its infrastructure, with many tunnels housing hidden military and civil defence facilities.
This integration reflects Switzerland’s preparedness and strategic engineering, combining transport efficiency with national security in an ingenious manner.
The Country with the Most Tunnels – China’s Expansive Network
China boasts more road tunnels than any other country, with thousands spread across its vast territory.
The nation’s rapid infrastructure development has seen an unprecedented expansion of its tunnel network, enabling faster and more efficient connections across mountains, rivers, and urban areas. This extensive network plays a critical role in supporting China’s growing transportation demands and economic growth.
The Eysturoy Tunnel – First Subsea Roundabout
Opened in 2020 in the Faroe Islands, the 11-kilometre Eysturoy Tunnel is the first in the world to incorporate a roundabout, and remains the only subsea roundabout in existence.
Situated 72 metres below sea level, the roundabout allows drivers to switch between multiple tunnel branches linking the capital, Tórshavn, with key towns on Eysturoy.
Beyond its practical function, the junction is enhanced with atmospheric lighting and artwork inspired by Faroese landscapes, making it both an engineering innovation and a unique driving experience beneath the ocean.
From the longest and deepest to the most dangerous and widest, road tunnels around the world showcase the extraordinary potential of modern engineering. Each tunnel represents a unique blend of innovation, necessity, and human perseverance.
For automotive enthusiasts and industry professionals, these structures are not just passages from one point to another—they are living testaments to our ability to reshape the world for safer, faster, and more efficient travel.
