Seoul Subway Line 4
Seoul Subway Line 4 (dubbed The Blue Line) of the Seoul Metropolitan Subway is a long line crossing from the southwest to the northeast across the Seoul National Capital Area. The central section in Seoul City is operated by Seoul Metro with through trains to Korail's Ansan and Gwacheon Lines. The southern terminus (Oido) is in Jeongwang 4-dong, Siheung City, and the northern terminus (Danggogae) is in Sanggye 4-dong, Nowon-gu, northern Seoul.
Line 4 | |
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Overview | |
Native name | 4호선(四號線) Sa Hoseon |
Type | Rapid transit |
System | Seoul Metropolitan Subway |
Status | Operational |
Termini | Danggogae Oido |
Stations | 48 26-Seoul Metro 22-Korail |
Operation | |
Opened | 20 April 1985 |
Operator(s) | Seoul Metro & Korail |
Technical | |
Line length | 72.1 km (44.8 mi) 31.7 km (19.7 mi) Seoul Metro[1] 40.4 km (25.1 mi) Korail[2] |
Number of tracks | 2 |
Electrification | 1,500 V DC & 25 kV AC (60 Hz) |
All northbound trains terminate at Danggogae, except during night time where they short-turn at various stations. Half of the southbound services short-turn at Sadang, and another half head to Oido or Ansan. Express train service stops at all stations between Danggogae and Sanbon, then at Sangnoksu, Jungang, Ansan, and all stations to Oido. The express service only operates during rush hours on weekdays.
History
1985:
- April 20: Line 4 is officially opened from Sanggye to Samseon-gyo.
1993:
- April 21: The line is extended northward from Sanggye to Danggogae.
1994:
- April 1: The line is extended southward from Sadang to Ansan when a section of the Gwacheon Line (from Seonbawi to Indeogwon) and Namtaeryeong Station open.
2000:
- July 28: The line is extended westward from Ansan to Oido.
2003
- July 18: Surisan Station opens as an in-fill station on the Ansan Line section.
2010
- Ansan Line AM express service is launched in the northbound direction only (starting from Ansan).
2014
- September 1: Southbound PM express service is launched (terminating at Ansan).
2017
- July 7: Express service is extended to Oido.
Future
The Transportation and Construction Committee of the National Assembly approved an extension from the northern end of Line 4 (Danggogae) to Jinjeop, Namyangju. Construction began on December 10, 2014 and is expected to be completed in May 2021.[3] In addition, express services will start skipping various stations north of Sanbon station by 2023 to cut travels times.[4]
Stations
Depots, junctions, and points of interest
(from Danggogae to Oido)
- Turnback siding (underground) after Danggogae Station
- Changdong Depot (used for Seoul Metro class 4000)
- Connecting track to Line 3 before Chungmuro Station
- Dongjak Bridge
- Chongshin Univ. – Sadang scissors crossover
- Hanyang University, ERICA Campus
- Turnback siding (underground) after Sadang Station
- Namtaeryong–Seonbawi track crossing point (flying crossover, switch from right to left-hand traffic, or vice versa)
- The voltage/current switches between DC 1,500 V ↔ AC 25,000 V
- Ansan Depot (used for simple maintenance of Korail Class 341000 train)
- Siheung Depot (used for Korail Class 341000 maintenance and also for heavy maintenance of Korail Class 311000 trains operated on Line 1)
- The largest scale of shell mounds in the South Korean west coast in Oido
Rolling stock
Current
Seoul Metro
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- Seoul Metro 4000 series
- MELCO VVVF-GTO inverter controlled electric car (fleet No. 401~409, 452~463)
- GEC-Alsthom VVVF-GTO inverter controlled electric car (fleet No. 410~426, 464, 465, 468, 469)
- Toshiba VVVF-IGBT inverter controlled electric car (fleet No. 466~467, 470~471)
- Dawonsys VVVF-IGBT inverter controlled electric car (fleet No. 451)
- Note: trains 401 to 426 are DC only and only allowed from Danggogae to Sadang
Korail
- Korail Class 341000 (ex-Korail Class 2030: 1st Batch, 2nd Batch)
- Note: only Korail trains are allowed to run commuter express trains from Oido to Sanbon
Former
Seoul Metro
- Seoul Metro 4000 series
- Wide-width GEC Chopper resister controlled electric car (1985–1993, temporary, built for Seoul Subway Line 3)
Korail
- Korail Class 1000 (Ansan Line only)
See also
- Subways in South Korea
- Seoul Metropolitan Subway
References
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Wikimedia Commons has media related to Seoul Subway Line 4. |
- 지하철건설현황 [Status of Subway Construction] (in Korean). Seoul City Government. Retrieved 22 February 2014.
- "Metro Lines & Trains in Operation". Korail. Retrieved 25 July 2014.
- "4호선 연장 및 창동차량기지 이전 공동 선언식" (Korean). 연합뉴스. 17 October 2012. Retrieved 5 November 2012.
- http://www.joongboo.com/news/articleView.html?mod=news&act=articleView&idxno=1178955