Tanna Tunnel
Encyclopedia
is a railroad
tunnel
in Shizuoka Prefecture
, Japan
operated by JR Central’s Tōkaidō Main Line
. This 7.8 km long tunnel shortened the trunk route between Tokyo
and Kobe
by omitting a detour round the mountains between Atami
and Numazu
.
avoided the Hakone mountains between Shizuoka and Kanagawa Prefecture
s by a long loop north to Gotemba, and then south to Numazu. This is the line now called the Gotemba Line and the same routing followed by the Tōmei Expressway
vehicular highway to this day.
Recognizing that this loop north through Gotemba was a major bottleneck in the rail system, the Japanese Railroad Ministry issued a contact in 1918 to the Kajima Corporation to build a tunnel. The project was heralded as a major public works
endeavor that would boost the Japanese economy out of its post-World War I
economic recession.
However, construction of the 7,804 meter long tunnel proved to be extremely difficult due to numerous unforeseen problems with the local geology
and contemporary tunneling technology. The Hakone mountain range is an active volcanic zone, containing a number of faults and is subject to frequent earthquake
s. In addition, workers encountered problems with a huge volume of water seepage, soft rock formations, and vents of hot spring water
. On April 1, 1920, a large section of the tunnel from the Atami side collapsed, trapping 42 workers, 17 of whom were rescued a week later after heroic efforts to dig them out. The tunnel was also damaged during the 1923 Great Kanto Earthquake
without fatalities; however, another section collapsed during an earthquake on February 26, 1930, killing five more workers. The work took many years more than initially anticipated, and costs far exceeded original budgetary estimates. The total number of workers killed in during construction was 67 men.
The two ends of the tunnel were finally joined on June 19, 1933 and the Tanna Tunnel was opened to rail traffic on March 10, 1934. It was the second longest tunnel in Japan at the time of its completion, having been surpassed by the Shimizu Tunnel
before it was completed.
The story of the construction of the Tanna Tunnel was the subject of a stage play by Hideji Hōjō in 1942.
The Tanna Tunnel remains in operation on the Tōkaidō Main Line to this day. Traffic on the Tōkaidō Shinkansen uses the parallel Shin-Tanna Tunnel (7,950m) completed in 1963.
Rail transport in Japan
Rail transport in Japan is a major means of passenger transport, especially for mass and high-speed travel between major cities and for commuter transport in metropolitan areas.-Overview:...
tunnel
Tunnel
A tunnel is an underground passageway, completely enclosed except for openings for egress, commonly at each end.A tunnel may be for foot or vehicular road traffic, for rail traffic, or for a canal. Some tunnels are aqueducts to supply water for consumption or for hydroelectric stations or are sewers...
in Shizuoka Prefecture
Shizuoka Prefecture
is a prefecture of Japan located in the Chūbu region on Honshu island. The capital is the city of Shizuoka.- History :Shizuoka prefecture was formed from the former Tōtōmi, Suruga and Izu provinces.The area was the home of the first Tokugawa Shogun...
, Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
operated by JR Central’s Tōkaidō Main Line
Tokaido Main Line
The is the busiest trunk line of the Japan Railways Group , connecting Tōkyō and Kōbe stations. It is long, not counting its many freight feeder lines around the major cities...
. This 7.8 km long tunnel shortened the trunk route between Tokyo
Tokyo
, ; officially , is one of the 47 prefectures of Japan. Tokyo is the capital of Japan, the center of the Greater Tokyo Area, and the largest metropolitan area of Japan. It is the seat of the Japanese government and the Imperial Palace, and the home of the Japanese Imperial Family...
and Kobe
Kobe
, pronounced , is the fifth-largest city in Japan and is the capital city of Hyōgo Prefecture on the southern side of the main island of Honshū, approximately west of Osaka...
by omitting a detour round the mountains between Atami
Atami, Shizuoka
is a city located in the eastern end of Shizuoka Prefecture, Japan. As of February 2010, the city has an estimated population of 39,755 and a population density of 645 people per km². The total area is 61.56 km².-Geography:...
and Numazu
Numazu, Shizuoka
is a city located in eastern Shizuoka Prefecture, Japan. As of 2009, the city has an estimated population of 205,636 and a population density of 1,100 persons per km². The total area was 187.11 km².- Geography:...
.
History
The initial routing of the Tōkaidō Main Line railway connecting Tokyo with OsakaOsaka
is a city in the Kansai region of Japan's main island of Honshu, a designated city under the Local Autonomy Law, the capital city of Osaka Prefecture and also the biggest part of Keihanshin area, which is represented by three major cities of Japan, Kyoto, Osaka and Kobe...
avoided the Hakone mountains between Shizuoka and Kanagawa Prefecture
Kanagawa Prefecture
is a prefecture located in the southern Kantō region of Japan. The capital is Yokohama. Kanagawa is part of the Greater Tokyo Area.-History:The prefecture has some archaeological sites going back to the Jōmon period...
s by a long loop north to Gotemba, and then south to Numazu. This is the line now called the Gotemba Line and the same routing followed by the Tōmei Expressway
Tomei Expressway
The is a national expressway on the island of Honshū in Japan. It is operated by Central Nippon Expressway Company. It is a part of Asian Highway Network -Naming:The word Tōmei is an acronym consisting of two kanji characters...
vehicular highway to this day.
Recognizing that this loop north through Gotemba was a major bottleneck in the rail system, the Japanese Railroad Ministry issued a contact in 1918 to the Kajima Corporation to build a tunnel. The project was heralded as a major public works
Public works
Public works are a broad category of projects, financed and constructed by the government, for recreational, employment, and health and safety uses in the greater community...
endeavor that would boost the Japanese economy out of its post-World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
economic recession.
However, construction of the 7,804 meter long tunnel proved to be extremely difficult due to numerous unforeseen problems with the local geology
Geology
Geology is the science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which it evolves. Geology gives insight into the history of the Earth, as it provides the primary evidence for plate tectonics, the evolutionary history of life, and past climates...
and contemporary tunneling technology. The Hakone mountain range is an active volcanic zone, containing a number of faults and is subject to frequent earthquake
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
s. In addition, workers encountered problems with a huge volume of water seepage, soft rock formations, and vents of hot spring water
Onsen
An is a term for hot springs in the Japanese language, though the term is often used to describe the bathing facilities and inns around the hot springs. As a volcanically active country, Japan has thousands of onsen scattered along its length and breadth...
. On April 1, 1920, a large section of the tunnel from the Atami side collapsed, trapping 42 workers, 17 of whom were rescued a week later after heroic efforts to dig them out. The tunnel was also damaged during the 1923 Great Kanto Earthquake
1923 Great Kanto earthquake
The struck the Kantō plain on the Japanese main island of Honshū at 11:58:44 am JST on September 1, 1923. Varied accounts hold that the duration of the earthquake was between 4 and 10 minutes...
without fatalities; however, another section collapsed during an earthquake on February 26, 1930, killing five more workers. The work took many years more than initially anticipated, and costs far exceeded original budgetary estimates. The total number of workers killed in during construction was 67 men.
The two ends of the tunnel were finally joined on June 19, 1933 and the Tanna Tunnel was opened to rail traffic on March 10, 1934. It was the second longest tunnel in Japan at the time of its completion, having been surpassed by the Shimizu Tunnel
Shimizu Tunnel
is a railroad tunnel in Gunma and Niigata Prefectures of Japan, operated by JR East Jōetsu Line. The name originates from the Shimizu mountain pass nearby...
before it was completed.
The story of the construction of the Tanna Tunnel was the subject of a stage play by Hideji Hōjō in 1942.
The Tanna Tunnel remains in operation on the Tōkaidō Main Line to this day. Traffic on the Tōkaidō Shinkansen uses the parallel Shin-Tanna Tunnel (7,950m) completed in 1963.