The first modern tunnel was built in London, in 1843 under the waters of the Thames. Dug twenty-three metres below the river surface and 396 metres in length, it was made using the “shield” technique. Ever since, humans have tried to work out how much and what is possible with a well-designed tunnel built using advanced techniques. New projects burgeoned, building longer and longer tunnels to allow the passage of horse-drawn carriages, pedestrians, trains and – later – automobiles. Today we are all accustomed to going through long tunnels, which have become a common, everyday occurrence. Nevertheless, tunnels are still fascinating precisely for the techniques, tools, investment and time required to build them. Today, we will be looking at the ten longest road tunnels on the planet. Hint: they’re all over thirteen kilometres long.
The World’s Longest Tunnels
Before kicking off with our list of the world’s longest road tunnels, it is worth noting that far longer tunnels exist, but rather than being built for road use, they are used as aqueducts, for railways and so on. By far the longest tunnel on the planet is the Delaware Aqueduct in New York State, which is an impressive 137 kilometres long and four metres in diameter.
Ranking of the World’s Ten Longest Road Tunnels
1 – Lærdal, Norway, between Lærdal and Aurland: measuring 24.51 kilometres in length, built in 2000.
2 – Yamate Tunnel, Japan, in Tokyo: measuring 18.2 kilometres in length, built in 2015.
3 – Zhongnanshan Tunnel, China, in Shaanxi: measuring 18.04 kilometres in length, built in 2017.
4 – Jinpingshan Tunnel, Sichuan, China: measuring 17.54 kilometres in length, built in 2011.
5 – St. Gotthard, Switzerland, between Göschenen and Airolo: measuring 16.84 kilometres in length, built in 1980.
6 – Tiantaishan Tunnel, China, in Shaanxi: measuring 15.56 kilometres in length, built in 2021.
7 – Ryfylke Tunnel, Norway, between Stavanger and Ryfylke: measuring 14.46 kilometres in length, built in 2019.
8 – Mount Ovit Tunnel, in Turkey, between Ikizdere and İspir: measuring 14.346 kilometres in length, built in 2018.
9 – Arlberg, Austria, between Vorarlberg and Tyrol: measuring 13.972 kilometres in length, built in 1978.
10 – Micangshan Tunnel, Sichuan, China: measuring 13.8 kilometres in length, built in 2018.
Interestingly, the oldest tunnels on the list of the world’s ten longest road tunnels are along the Alpine arc, in Switzerland and Austria. The top ten is largely dominated by China, which has built many long tunnels over the last decade, two in Sichuan alone.
The World’s Longest Road Tunnel: Lærdal, 24.51 kilometres long
The world’s longest road tunnel is in Western Norway, between Lærdal and Aurland. To get an idea of how long it is, it’s twenty-two kilometres by autostrada from Reggio Emilia and Moderna Nord, 2.5 kilometres less than the length of this gigantic road tunnel. Construction work began in 1995 and was completed in 2000, the year it officially opened. This single two-bore tunnel cost more than NOK 1 billion to build. It is not surprising that Norway has two tunnels on the list of the ten longest on the planet: with a coastline full of fjords, getting around presents a host of complex challenges. For Lærdal, rather than allocating funds to upgrade existing roads, the Norwegian parliament preferred to invest in building the world’s longest road tunnel. Given the long travel time of roughly twenty minutes, great care was lavished on road lighting to minimize inconvenience and stress for motorists. As a result, driving through the tunnel feels like driving in daylight. Boring the tunnel required extracting some 2.5 million cubic metres of rock.
Yamate Tunnel, the World’s Second Longest
At 18.2 kilometres in length, the Yamate Tunnel is the second longest road tunnel in the world. Building work took a long time, from 1992 to 2015, as individual sections were design, built and opened in different years.
Zhongnanshan and Jinpingshan Tunnels in China
Rounding out the podium of the world’s longest tunnels is the Zhongnanshan Tunnel in China. Just over eighteen kilometres long, this 2-bore tunnel runs below Zhongnan Mountain. Construction work began in 2002 and was completed in 2007. The tunnel reaches a maximum depth of 1,640 metres below the mountain’s surface.
Just off the podium in fourth place, the Jinpingshan Tunnel, located near Sichuan, measures 17.5 kilometres in length. This tunnel leads to the Jinping Dam, the highest in the world, so two of the world’s most breathtaking engineering works built in recent years are in the same small area. Unlike the others in this list, the tunnel is only accessible to authorized vehicles; it is closed to normal automobile transit.
The Gotthard Road Tunnel
We close with the 16.84 kilometre-long Gotthard road tunnel (not to be confused with the Gotthard railway tunnel). From when it opened in 1980 to 2000, it was the world’s longest road tunnel, connecting the villages of Göschenen in the canton of Uri with Airolo in Canton Ticino, making it possible to cross the Gotthard massif far faster than via the pass. Construction of the road tunnel took ten years, from May 1970 to September 1980. In 2016, in a referendum 57 percent of the Swiss people voted in favour of building a second road tunnel.