The longest undersea tunnel in the world


Hokkaido, formerly known as Ezo, is the second largest island of Japan and locates at the northernmost of its
47 prefectures. The Tsugaru Strait separates Hokkaido from Honshu, although the two islands are connected
by the underwater SeikanTunnel. The capital is Sapporo, the most populated city in Hokkaido. The population
of Hokkaido is about 5,470,000 in 2019.

(L) The island of Hokkaido (R) Lake Toya, a volcanic lake in Hokkaido The 2008 G8 Summit was held here.

The Hokkaido Railway Company is one of the constituent companies of Japan Railways Group, and thus often known
as JR-Hokkaido. It operates inter-city-rail services in Hokkaido. A privatization from Government-owned railway is
carried out in 1987. The length of railway tracks operated at that time was over 3,000 km. This has dwindled to below
2,500 km, as unprofitable lines have been shut down. The ferry service has been replaced by the Seikan Tunnel.
Hokkaido Railway's headquarter is located in Sapporo.

(L) Red line indicates the Seikan Tunnel, the world's longest undersea tunnel.
(R) Satellite picture of Hokkaido

(L) Aomori-side entrance of Seikan Tunnel (R) Illustration of the under-sea tunnel
Now, Shinkansen super-express train only runs between Aomori and Hakodate: The travel time from Tokyo to Hakodate is four hours.

Hakodate-side exit of Seikan Tunnel (Picture source: BS Asahi )

The Seikan Tunnel is a 53.85 km railway tunnel, with a 23.3 km long portion under the seabed.
Track level is about
140 meters below the seabed and 240 meters below sea level. It is the longest undersea tunnel in the world.
However, the Channel Tunnel, which connects the land of United Kingdom and France, has a longer under-sea portion.
The train of Kaikyo Line travels beneath the Tsugaru Syrait, which lays between the Aomori Prefectute of Honshu island
and the island of Hokkaido.

Undersea station in the tunnel connecting the northern Honshu and Hokkaido:
The pictures were taken in October 2012. Here is not open to the general public anymore.

津軽海峡線特急車窓 2012
An express train is linking northern Honshu and Hokkaido through the undersea tunnel.

Hokkaido Railway Company

Gotthard Base Tunnel, between Swiss and Italia


Asahiyama Zoo, Hokkaido

Asahikawa 2018
Sapporo 2018
Hakodate 2018
Railway Travel from Sapporo to Hakodate, via Kutchan, Hokkaido
Smoking Ban in JR Hokkaido Trains

A smoke-free railway that runs a beautiful Hokkaido

Three major Japanese railway companies think that the smoking car and/or smoking booth
in a train are the superb service to train passengers.

JR-East Railway
An anti-smoking measurer of the JR-Tokai and JR-West is really putting the clock back!
The Japanese Government does not prohibit smoking in a train vehicle.

The smoking room in the train infringes the health of the passengers.

Kinki-Nippon Railway company still operates smoking vehicles.
The railway company leading a passenger to health damage

The smoking room in the train adversely affects the health of the passengers.


2006年10月執筆 2009年9月加筆 2012年12月加筆 2020年6月再編集
執筆 医学博士 宮本順伯
The article was written in October 2006, and revised in September 2009 and December 2012,
and two pictures were added in October 2012,
and last revised in June 2020,
by Junhaku Miyamoto, M.D., PhD.


Railway Travel from Sapporo to Hakodate, via Kutchan, Hokkaido

Special Note: 日本語表示

 Russia unduly occupies our Northern Territories of Japan.
 Smoke-free hotels in Japan
Domestic travel in Japan
 WHO: Smoking should be banned in all public spaces.
 World population: seven billion v.s. Declining birth rate in Japan
 Nobody in the earth can destroy the natural beauty of the land.
 Stop merging war criminals and war victims at Yasukuni Shrine.
 Tax saving's rental housing is mushrooming.

Copyright (C) 2006-2022 Junhaku Miyamoto, PhD. All right is reserved.
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