Great Seto Bridge
{{Short description|Major bridge connecting Honshū and Shikoku}}
{{Refimprove|date=June 2009}}
{{Infobox Bridge
| bridge_name = {{nihongo|Great Seto Bridge
|瀬戸大橋|Seto Ōhashi}}
| image = Seto-Ohashi Bridge.jpg
| caption = Great Seto Bridge from Honshū (left) via the islands of Hitsuishijima and Yoshima to Shikoku
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| also_known_as =
| carries = 4 lanes of File:JP Expressway E30.svg Seto-Chūō Expressway (upper)
2 rail lines (lower)
| crosses = Seto Inland Sea
| maint = Honshu-Shikoku Bridge Expressway Company
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| design = Double-decked bridge system
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| length = {{convert|13.1|km|abbr=on}}
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| open = {{start date and age|1988|4|10}}
| closed =
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| coordinates = {{Coord|34|23|54|N|133|48|36|E|type:landmark_region:JP_source:dewiki|display=inline,title}}
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The {{nihongo|Great Seto Bridge or Seto Ohashi Bridge|瀬戸大橋|Seto Ōhashi}}{{Cite web|title=英語表記のガイドライン（香川県）|trans-title=English Guidelines (Kagawa Prefecture)|url=https://www.pref.kagawa.lg.jp/kokusai/data_book/sonota/guidelines.html|access-date=17 February 2021|website=香川県 (Kagawa Prefecture)}}{{NoteTag|"Seto-Ohashi" is the term used on e.g. Google Maps}} is a series of double deck bridges connecting Okayama and Kagawa prefectures in Japan across a series of five small islands in the Seto Inland Sea. Built over the period 1978–1988, it is one of the three routes of the Honshū–Shikoku Bridge Project connecting Honshū and Shikoku islands and the only one to carry rail traffic. The total length is {{convert|13.1|km|sp=us}}, and the longest span, the Minami Bisan-Seto Bridge, is {{Convert|1,100|m|ft|abbr=on|sp=us}}.
Crossing the bridge takes about 20 minutes by car or train. The ferry crossing before the bridge was built took about an hour.
The bridges carry two lanes of highway traffic in each direction (Seto-Chūō Expressway) on the upper deck and one railway track in each direction (Seto-Ōhashi Line) on the lower deck. The lower deck was designed to accommodate an additional set of Shinkansen tracks for a proposed construction of the Shikoku Shinkansen line to Shikoku.{{Cite web|title=北陸新幹線の新大阪駅、その先をどうするか|url=https://www.itmedia.co.jp/business/articles/1703/17/news019_4.html|access-date=2021-06-03|website=ITmedia ビジネスオンライン|language=ja}}
History
[[File:Map of Honshu-Shikoku Bridge Project.svg|thumb|Green: Great Seto Bridge
Yellow: Kobe-Awaji-Naruto Expressway
Red: Nishiseto Expressway]]
When in 1889 the first railway in Shikoku was completed between Marugame and Kotohira, a member of the Prefectural Parliament, {{nihongo|Jinnojo Ōkubo|大久保諶之丞|Ōkubo Jinnojo|extra=1849–1891}}, stated in his speech at the opening ceremony: "The four provinces of Shikoku are like so many remote islands. If united by roads, they will be much better off, enjoying the benefits of increased transportation and easier communication with each other."{{citation needed|date=May 2013}}
While it took a century for this vision of a bridge across the Seto Inland Sea to become reality, another of Ōkubo's ideas, mentioned in a drinking song he composed, was accomplished twenty years sooner:
:I'll tell you, dear, don't laugh at me,
:a hundred years from now, I'll be seeing you
:flying to and from the moon in a space ship.
:Its port, let me tell you, dear,
:will be that mountaintop over there![https://www.city.mitoyo.lg.jp/kakuka/kyouikuiinkai/shogai/1/1920.html]
The bridge idea lay dormant for about sixty years. In 1955, after 171 people, including 100 students from elementary and junior high schools on school trips, died when two ferries collided in dense fog off the coast of Takamatsu, a safer crossing was deemed necessary. By 1959, meetings were held to promote building the bridge. Scientists began investigations shortly after, and in 1970, the Honshu-Shikoku Bridge Construction Authority was inaugurated. However, work was postponed for five years by the "1973 oil shock"; once the Environment Assessment Report was published in 1978, construction got underway. The ferry disaster also led to the creation of the Akashi Kaikyō Bridge.
The project took ten years to complete at a cost of US$7 billion; {{convert|3.646|e6m3|abbr=off|sp=us}} of concrete and 705,000 tons of steel were used in construction.{{citation needed|date=May 2013}} Although nets, ropes and other safety measures were employed, 17 workers were killed during the 10 years of construction.
The bridge opened to road and rail traffic on April 10, 1988 by then-Crown Prince Akihito.{{cite news |title=Longest road-rail bridge opens |url=https://eresources.nlb.gov.sg/newspapers/digitised/article/straitstimes19880411-1.2.16.19?qt=seikan,%20tunnel&q=seikan%20tunnel |work=The Straits Times |agency=Reuters, AFP |date=11 April 1988}} At opening time, the toll fee for a one-way drive on the bridge's highway cost ¥ 6300.
Constituent bridges
File:Great Seto Bridge - Aug 17 2017.webm
File:Shimotsui-Seto Bridge who saw from Okayama Prefecture.JPG
File:JP-Okayama-Great-Seto-Bridge-Panoramic-View.JPG
Six of the eleven bridges are separately named, unlike some other long bridge complexes such as the San Francisco–Oakland Bay Bridge. The other five bridges are viaducts. The six named bridges from north to south are listed below.
;Shimotsui-Seto Bridge: The {{nihongo|Shimotsui-Seto Bridge|{{coord|34|25|51|N|133|48|22.4|E|region:JP_type:landmark_source:ja|display=inline}} 下津井瀬戸大橋|Shimotsui Seto Ō-hashi}} is a double-decked suspension bridge with a center span of {{convert|940|m|ft|sp=us}} and a total length of {{convert|1400|m|ft|sp=us}} which connects Honshū with the island of Hitsuishijima. It is the 45th largest suspension bridge in the world. It is the northernmost bridge of the Seto-Chuo Expressway.
;Hitsuishijima Bridge: The {{nihongo|Hitsuishijima Bridge|{{coord|34|24|35|N|133|48|25.6|E|region:JP_type:landmark_source:ja|display=inline}} 櫃石島橋|Hitsuishijima-kyō}} is a double-decked cable-stayed bridge with a center span of {{convert|420|m|ft|sp=us}} and a total length of {{convert|790|m|ft|sp=us}}. It is immediately north of the identical Iwakurojima Bridge.
;Iwakurojima Bridge: The {{nihongo|Iwakurojima Bridge|{{coord|34|24|06.3|N|133|48|33|E|region:JP_type:landmark_source:ja|display=inline}} 岩黒島橋|Iwakurojima-kyō}} is a double-decked cable-stayed bridge with a center span of {{convert|420|m|ft|sp=us}} and a total length of {{convert|790|m|ft|sp=us}}. It is immediately south of the identical Hitsuishijima Bridge.
;Yoshima Bridge: The {{nihongo|Yoshima Bridge|{{coord|34|23|37.2|N|133|48|45.2|E|region:JP_type:landmark_source:ja|display=inline}} 与島橋|Yoshima-kyō}} is a continuous double-decked truss bridge with a main span of {{convert|246|m|ft|sp=us}} and a total of five spans with a length of {{convert|847|m|ft|sp=us}}. It is immediately south of the Hitsuishijima and Iwakurojima Bridges.
;Kita Bisan-Seto Bridge: The {{nihongo|Kita Bisan-Seto Bridge|{{coord|34|23|43.5|N|133|49|13.7|E|region:JP_type:landmark_source:ja|display=inline}} 北備讃瀬戸大橋|Kita Bisan Seto Ō-hashi}} is a double-decked suspension bridge with two sections linked by a common anchorage between them. The center span is {{convert|990|m|ft|0|sp=us}} and the total length is {{convert|1538|m|ft|0|abbr=on}}. It is the 19th largest suspension bridge in the world. The nearly identical Minami Bisan Seto Bridge is located immediately to the south.
;Minami Bisan-Seto Bridge: The {{nihongo|Minami Bisan-Seto Bridge|{{coord|34|21|51|N|133|49|31|E|region:JP_type:landmark_source:ja|display=inline}} 南備讃瀬戸大橋|Minami Bisan Seto Ō-hashi}} is a double-decked suspension bridge with a center span of {{convert|1100|m|ft|0|sp=us}} and a total length of {{convert|1648|m|ft|0|abbr=on}}. It is the 13th longest suspension bridge span in the world. It is the southernmost part of the Great Seto Bridge. The roadway of the bridge is {{convert|93|m|sp=us}} above sea level.{{Citation needed|date=November 2009}}
Sister bridges
File:SetoBridgePlaque.jpg in San Francisco, California, United States]]
- Golden Gate Bridge, San Francisco, California, United States
- Affiliated from April 5, 1988
- Fatih Sultan Mehmet Bridge, Istanbul, Turkey
- Affiliated from July 3, 1988
- Øresund Bridge, Malmo, Sweden and Copenhagen, Denmark
- Affiliated from May 24, 2008{{nihongo|2008 Press Release|[http://www.jb-honshi.co.jp/press/080520press-1.html 2008年プレスリリース] {{cite web |url=http://www.jb-honshi.co.jp/press/080520press-1.html |title=Jb本四高速：2008年プレスリリース：瀬戸大橋とオーレスン橋の姉妹橋調印式について |access-date=2010-07-04 |url-status=dead |archive-url=https://web.archive.org/web/20081212222815/http://www.jb-honshi.co.jp/press/080520press-1.html |archive-date=2008-12-12 |language=ja}}}}. JB本四高速 (Honshu-Shikoku Bridge Expressway Company). Accessed February 24, 2010.
See also
- Honshū–Shikoku Bridge Project, three routes connecting Honshu and Shikoku
- Akashi Kaikyō Bridge
- Kurushima Kaikyō Bridge
- Tsing Ma Bridge, which has the longest road-rail span in the world
- List of largest suspension bridges
- List of largest cable-stayed bridges
- Mount Washu, viewpoint of the Great Seto Bridge
Notes
{{NoteFoot}}
References
{{Reflist}}
External links
{{Commons category|Great Seto Bridge}}
{{refbegin}}
* [http://www.jb-honshi.co.jp/english/index.html Honshū-Shikoku Bridge Authority homepage]
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- [https://www.google.com/maps/place/Shikoku/@34.0333162,133.4395586,128596m/data=!3m1!1e3!4m5!3m4!1s0x3551e76a6585fd45:0xd4602fd80d0ed59d!8m2!3d33.7432238!4d133.6375314?hl=en Google Earth view of the strait between Shikoku and Honshu]
- [https://www.google.com/maps/place/Seto+Bridge/@34.3735421,133.8071373,15687m/data=!3m1!1e3!4m5!3m4!1s0x60036880ed444d51:0x5087828ac86e2b5d!8m2!3d35.2238818!4d137.0959774?hl=en Google Earth view of the Great Seto Bridge]
Category:Railway bridges in Japan
Category:Suspension bridges in Japan
Category:Cable-stayed bridges in Japan
Category:Bridges completed in 1988
Category:Truss bridges in Japan
Category:Transport buildings and structures in Kagawa Prefecture
Category:Transport buildings and structures in Okayama Prefecture
Category:Roads in Kagawa Prefecture
Category:Roads in Okayama Prefecture
Category:Toll bridges in Japan