The famous Khun Tan Tunnel

Entrance of railway tunnel Thailand Railway Journeys

The famous Khun Tan Tunnel

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The Khuntan Tunnel is with a length of 1,362 meters the longest railway tunnel in Thailand. You pass through this tunnel on the Northern Line of the State Railway of Thailand between Bangkok and Chiang Mai. It is 683 km from Bangkok and 68 km before Chiang Mai. The tunnel is located in the Khuntan or Khun Tan National Park.

The most beautiful part of the Northern Line is stretch through the Khun Tan National Park. To fully enjoy the scenery and the tunnel you have to take the day train. The overnight train passes through this area sometimes after dark, depending on the train you take and on the season. The trains only stop briefly at the Khun Tan Railway Station so you will not have time to make a picture of the tunnel. The Khun Tan tunnel features in all our railway journeys.

Railway station in the forest Khun Tan Tunnel
Khun Tan railway station

Construction of the Khun Tan Tunnel

Construction of the tunnel started in 1907 and was completed in 1918. It took approximately 11 years to finish the job. A German engineer named Emil Eisenhofer supervised its construction. Khun Chowng-liang Lue-kiat, a respected muslim merchant from Chiang Mai, played an important role in the supply and logistics of the construction.

The construction of the tunnel was a herculean task. The construction was in the middle of the jungle, a very unwelcome environment for human beings. In those days there still was dangerous wildlife in the mountains. There were not only tigers but also snakes, leeches and other unfriendly animals. Moreover, more than one thousand workers died of malaria or cholera. According to a Thai language source 90% of the workers were Chinese.

Khuntan tunnel

Reginald Le May visits Khun Tan

British diplomat Reginald Le May visited the construction site in 1913 on his way from Chiang Mai to Lampang. He contradicts the statement that 90% of the workers were Chinese.

“The coolies at work were all Lao*. I was told that Chinamen would be too costly as, although they are harder workers, they ask more than double the pay. Those working inside the tunnel received on the average nearly a tidal a day, or about ten shillings a week. The prospect would hardly appeal to an English navvy**, but then the Lao coolie can live comfortably on ten shillings a month.”

* Frans: the people in North Thailand were known as “Lao” before World War Two.
* Frans:  a laborer employed in the excavation and construction of a road, railroad, or canal.

People working on a tunnel Khun Tan Tunnel
Construction of the Khun Tan tunnel. Source: the internet

Siam declares war on Germany

World War One interrupted the construction. For various reasons, Siam (Thailand) declared war on Germany and Austria-Hungary on July 22, 1917, and entered World War One. Consequently, they interned the Germans working on the construction of the tunnel for the duration of the war. After the war Italian engineers oversaw the completion of the Khun Tan Tunnel. On January 1, 1922, the Bangkok – Chiang Mai railway line, and the Khun Tan Tunnel, were officially opened.

Construction of tunnel
Construction of the Khuntan Tunnel

The life of Emil Eisenhofer

During his internment Emil Eisenhofer spent six months in Thailand and two years in India. He returned to Germany and then accepted a job in Turkey, shortly before meeting Irmgard who became his wife.
After being in Turkey for three years, Emil received a draft for 14 months pay from the State Railway of Thailand as reparation for the loss of his job and personal belongings. He was so delighted that he left Turkey and returned to Germany to find a way back to Thailand.

In 1930 they returned to Thailand and stayed there until Emil’s passing in 1962. During their years in Siam (and later Thailand), the Eisenhofers had seen three kings, a revolution and a dozen coups d’etat. Because of his work on the construction of the tunnel, authorities allowed Emil’s final resting place to be places at the northern end of the Khun Tan railway tunnel. A small memorial for Mr. and Mrs. Eisenhofer was erected there.

Shrine of man with picture Khun Tan Tunnel
Emil Eisenhofer Memorial at Khun Tan
Train coming out of a tunnel Khun Tan Tunnel
Khun Tan Tunnel in the 1960s

Sources of this article

I have made numerous train trips in Thailand. Most of them were on the Northern Line.

B.R.Whyte, The Railway Atlas of Thailand, Laos and Cambodia, Bangkok, 2010.

R.Ramaer, The Railways of Thailand, Bangkok, 2009.

Reginald Le May, An Asian Arcady, (An Account of Northern Siam), Bangkok,1926

Boonserm Satrabhaya, Picture Trails, website Chiang Mai University Library



The location of the Khun Tan Railway Tunnel

It is possible to drive to the Khun Tan Railway Tunnel. The tunnel is about 73 km from Chiang Mai. Along the way you can visit the iconic White Railway Bridge. There is also a walking trail from the visitor center of Khun Tan National Park to the station.

The Khun Tan Railway Tunnel features in these tours