# Seohaean Expressway

The Seohaean Expressway (Korean: 서해안 고속도로; Seohaean Gosok Doro), meaning "West Coast Expressway", is a freeway in South Korea, connecting Mokpo to Gunsan, Dangjin, and Seoul.
It is numbered 15. The entire length from Seoul to Mokpo is 345 km and the posted speed limit is 110 km/h, enforced primarily by speed cameras. It is connected of Seohae Grand Bridge in Pyeongtaek to Dangjin.
The branch expressways of the Seohaean Expressway are Seocheon–Gongju Expressway and Pyeongtaek–Siheung Expressway.
Typical facilities of this expressway is Seohae Bridge(Korean: 서해대교; Seohae Daegyo) which the total length of 7.3 km linking the Pyeongtaek(Gyeonggi Province) and Dangjin(Chungnam Province). The bridge is the third long bridge in the Republic of Korea.
The highway is a major highway linking the Seohaean Region(서해안권) for the first north–south axis (남북 제1축), the road through the South Jeolla Province, North Jeolla Province, South Chungcheong Province, Gyeonggi Province.

## History

* December 1991 – Construction begin
* May 1993 – Construction begin of Seohae Grand Bridge
* 6 July 1994 – Seoul–Ansan segment opened to traffic.
* 17 December 1996 – Ansan–Pyeongtaek segment opened to traffic.
* 25 August 1998 – Mokpo–Muan segment opened to traffic.
* 30 October 1998 – Gunsan–Seocheon segment opened to traffic.
* 10 November 2000 – Seohae Grand Bridge segment opened to traffic. and Pyeongtaek–Dangjin segment opened to traffic.
* 27 September 2001 – Dangjin–Seocheon segment opened to traffic.
* 21 December 2001 – The last segment, Gunsan–Muan segment opened to traffic.
* 30 July 2010 – Work begins to widen to 8 lanes in Ansan–Iljik Junction.
* 23 November 2011 – Jungnim Junction opened to traffic.
* October 2014 – Seohae Bridge – W. Pyeongtaek Junction Section (10.3 km) road expansion started construction.
* November 2014 – The 10-lane expansion of the Ansan JCT – Jonam JCT (2.9 km) section was completed.
* June 2015 – The 10-lane expansion of the Jonam JCT – Mokgam IC (3.2 km) section was completed.
* 23 December 2015 – The 10-lane expansion of the Mokgam IC – Iljik JCT (3.8 km) section was completed.
* 3 July 2016 – Soha Junction opened to traffic.

## Compositions
### Lanes

* Mokpo IC – Dangjin JC, Iljik JC-West Seoul End: 4
* Dangjin JC – Bibong IC, Maesong IC-Ansan JC, Jonam JC–Mokgam IC: 6
* Mokgam IC – Iljik JC, Bibong IC – Maesong IC, West Seoul TG-Jonam JC: 8
* Ansan-Iljik, Yangjae-Giheung, unjung Bridge and Seoul Ring Road (Rigid Pavement) 130 km JC – : 10

### Length

346.1 km (215.1 mi)

### Speed limits

* Jungnim JC – Maesong IC : 110 km/h
* Maesong IC – Seoul(Geumcheon) : 100 km/h
* Mokpo – Jungnim JC : 90 km/h

## List of facilities

* IC: Interchange, JC: Junction, SA: Service area, TG:Tollgate
| No. | Name | Korean name | Hanja name | Connections | Distance | Distance | Notes | Location | Location |
| Connected directly with National Route 1, National Route 2(Goha-daero)(고하대로) ||||||||||
| | Mokpo | 목포 시점 | 木浦 始點 | National Route 1 National Route 2 Mokpo Bridge Aphae Bridge | – | 0.0 | | Mokpo | Jeonnam |
| 1 | Mokpo IC | 목포나들목 | 木浦나들목 | National Route 1 (Yeongsan-ro) | 0.26 | 0.26 | | Mokpo | Jeonnam |
| | Jungnim JC | 죽림분기점 | 竹林分岐點 | Namhae Expressway (Mokpo–Gwangyang) National Route 2 Jeonnam Provincial Office Mokpo Airport | 3.90 | 4.16 | | Muan | Jeonnam |
| 2 | Illo IC | 일로나들목 | 一老나들목 | Local Route 815 | 2.10 | 6.26 | | Muan | Jeonnam |
| TG | Mokpo TG | 목포요금소 | 木浦料金所 | | | | Main Tollgate | Muan | Jeonnam |
| 3 | Muan IC | 무안나들목 | 務安나들목 | National Route 1 | 17.28 | 23.54 | | Muan | Jeonnam |
| 4 | Hampyeong JC | 함평분기점 | 咸平分岐點 | Muan-Gwangju Expressway Muan International Airport | 2.46 | 26.00 | | Hampyeong | Jeonnam |
| SA | Hampyeong -cheonji SA | 함평천지휴게소 | 咸平天地休憩所 | | | | Mokpo-bound only | Hampyeong | Jeonnam |
| 5 | Hampyeong IC | 함평나들목 | 咸平나들목 | National Route 23 | 7.81 | 33.81 | | Hampyeong | Jeonnam |
| SA | Hampyeong -cheonji SA | 함평천지휴게소 | 咸平天地休憩所 | | | | Seoul-bound only | Hampyeong | Jeonnam |
| 5-1 SA | Bulgapsan Yeonggwang SA | 부안고려청자휴게소 | | | | | Muan-bound only (temporary rest area, no gas station) Hi-pass exclusive interchange | Yeonggwang | Jeonnam |
| 6 | Yeonggwang IC | 영광나들목 | 靈光나들목 | National Route 23 | 24.33 | 58.14 | | Yeonggwang | Jeonnam |
| 7 | Gochang JC | 고창분기점 | 高敞分岐點 | Gochang-Damyang Expressway | 16.06 | 74.20 | | Gochang | Jeonbuk |
| 8 | Gochang IC | 고창나들목 | 高敞나들목 | Local Route 15 | 2.74 | 76.94 | | Gochang | Jeonbuk |
| SA | Gochang Goindol SA | 고창고인돌휴게소 | 高敞고인돌休憩所 | | | | | Gochang | Jeonbuk |
| 9 | Seonunsan IC | 선운산나들목 | 禪雲山나들목 | National Route 22 Seonunsa | 7.91 | 84.85 | | Gochang | Jeonbuk |
| 10 | Julpo IC | 줄포나들목 | 茁浦나들목 | Local Route 710 | 9.87 | 94.72 | | Buan | Jeonbuk |
| 11 | Buan IC | 부안나들목 | 扶安나들목 | National Route 30 | 16.18 | 110.90 | | Buan | Jeonbuk |
| 12 | W Gimje IC | 서김제나들목 | 西金堤나들목 | National Route 29 Saemangeum-Jeonju Expressway (December 2021) Saemangeum | 13.93 | 124.83 | | Gimje | Jeonbuk |
| 13 | E Gunsan IC | 동군산나들목 | 東群山나들목 | National Route 21 National Route 26 National Route 29 | 12.55 | 137.38 | | Gunsan | Jeonbuk |
| SA | Gunsan SA | 군산휴게소 | 群山休憩所 | | | | Mokpo-bound only | Gunsan | Jeonbuk |
| 14 | Gunsan IC | 군산나들목 | 群山나들목 | National Route 21 | 8.40 | 145.78 | | Gunsan | Jeonbuk |
| SA | Gunsan SA | 군산휴게소 | 群山休憩所 | | | | Seoul-bound only | Gunsan | Jeonbuk |
| 15 | E Seocheon JC | 동서천분기점 | 東舒川分岐點 | Seocheon-Gongju Expressway | 6.23 | 152.01 | | Seocheon | Chungnam |
| 16 | Seocheon IC | 서천나들목 | 舒川나들목 | National Route 4 | 8.98 | 160.99 | | Seocheon | Chungnam |
| SA | Seocheon SA | 서천휴게소 | 舒川休憩所 | | | | | Seocheon | Chungnam |
| 17 | Chunjangdae IC | 춘장대나들목 | 春長臺나들목 | National Route 21 | 11.91 | 172.90 | | Seocheon | Chungnam |
| 18 | Muchangpo IC | 무창포나들목 | 武昌浦나들목 | Local Route 606 | 8.71 | 181.61 | | Boryeong | Chungnam |
| 19 | Daecheon IC | 대천나들목 | 大川나들목 | National Route 36 Daecheon Beach | 11.99 | 193.60 | | Boryeong | Chungnam |
| SA | Daecheon SA | 대천휴게소 | 大川休憩所 | | | | | Boryeong | Chungnam |
| 20 | Gwangcheon IC | 광천나들목 | 廣川나들목 | Local Route 96 | 19.72 | 213.32 | | Hongseong | Chungnam |
| SA | Hongseong SA | 홍성휴게소 | 洪城休憩所 | | | | | Hongseong | Chungnam |
| 21 | Hongseong IC | 홍성나들목 | 洪城나들목 | National Route 29 | 10.80 | 224.12 | | Hongseong | Chungnam |
| 22 | Haemi IC | 해미나들목 | 海美나들목 | National Route 45 Haemieupseong | 13.68 | 237.80 | | Seosan | Chungnam |
| SA | Seosan SA | 서산휴게소 | 西山休憩所 | | | | | Seosan | Chungnam |
| 23 | Seosan IC | 서산나들목 | 西山나들목 | National Route 32 | 10.78 | 248.52 | | Seosan | Chungnam |
| 24 | Dangjin JC | 당진분기점 | 唐津分岐點 | Dangjin-Yeongdeok Expressway | 6.56 | 255.08 | | Dangjin | Chungnam |
| 25 | Dangjin IC | 당진나들목 | 唐津나들목 | National Route 34 | 9.39 | 264.47 | | Dangjin | Chungnam |
| 26 | Songak IC | 송악나들목 | 松岳나들목 | National Route 38 Dangjin Steelworks | 8.07 | 272.54 | | Dangjin | Chungnam |
| SA | Haengdam Island SA (Ocean Park Resort) | 행담도휴게소 | 行淡島休憩所 | | | | In the Seohae Grand Bridge | Dangjin | Chungnam |
| BR | Seohae Bridge | 서해대교 | 西海大橋 | | | | | Pyeongtaek | Gyeonggi |
| 27-1 | Poseung JC | 포승분기점 | 浦升分岐點 | 20px Iksan–Pyeongtaek Expressway Branch | | | | Pyeongtaek | Gyeonggi |
| 27 | W Pyeongtaek IC | 서평택나들목 | 西平澤나들목 | National Route 82 | 12.64 | 285.18 | | Pyeongtaek | Gyeonggi |
| 28 | W Pyeongtaek JC | 서평택분기점 | 西平澤分岐點 | Pyeongtaek–Jecheon Expressway Pyeongtaek-Siheung Expressway | 6.53 | 291.71 | | Pyeongtaek | Gyeonggi |
| 29 | Baran IC | 발안나들목 | 發安나들목 | National Route 39 | 7.82 | 299.53 | | Hwaseong | Gyeonggi |
| 29-1 | Paltan JC | 팔탄분기점 | 八灘分岐點 | Capital Region Second Ring Expressway | | | | Hwaseong | Gyeonggi |
| SA | Hwaseong SA | 화성휴게소 | 華城休憩所 | | | | | Hwaseong | Gyeonggi |
| 30 | Bibong IC | 비봉나들목 | 飛鳳나들목 | National Route 39 | 13.62 | 313.15 | | Hwaseong | Gyeonggi |
| SA | Maesong SA | 매송휴게소 | 梅松休憩所 | | | | | Hwaseong | Gyeonggi |
| 31 | Maesong IC | 매송나들목 | 梅松나들목 | Local Route 84 | 4.02 | 317.17 | | Hwaseong | Gyeonggi |
| 31-1 | Palgok JC | 팔곡분기점 | 八谷分岐點 | Yeongdong Expressway | 3.80 | 320.97 | Mokpo-bound enter only Gangneung-bound exit only | Ansan | Gyeonggi |
| 32 | Ansan JC | 안산분기점 | 安山分岐點 | Yeongdong Expressway | 5.12 | 326.09 | | Ansan | Gyeonggi |
| TG | W. Seoul TG | 서서울요금소 | 西서울料金所 | | | | Main Tollgate | Ansan | Gyeonggi |
| 33 | Jonam JC | 조남분기점 | 鳥南分岐點 | Capital Region First Ring Expressway | 2.89 | 328.98 | | Siheung | Gyeonggi |
| SA | Mokgam SA | 목감간이휴게소 | 牧甘簡易休憩所 | | | | Seoul-bound only | Siheung | Gyeonggi |
| 34 | Mokgam IC | 목감나들목 | 牧甘나들목 | National Route 42 Suwon–Munsan Expressway 3rd Gyeongin Highway | 3.16 | 332.14 | | Siheung | Gyeonggi |
| 35 | Gwangmyeong Stn. IC | 광명역나들목 | 光明驛나들목 | Ori-ro KTX Gwangmyeong Stn. | 1.15 | 333.29 | | Anyang | Gyeonggi |
| 36 | Iljik JC | 일직분기점 | 日直分岐點 | 2nd Gyeongin Expressway | 2.67 | 335.96 | | Gwangmyeong | Gyeonggi |
| 37 | Soha JC | 소하분기점 | 所下分岐點 | Suwon-Munsan Expressway Gangnam Beltway | | | Gangnam-bound only Mokpo-bound only | Geumcheon | Seoul |
| 38 | Geumcheon IC | 금천나들목 | 衿川나들목 | National Route 1 Doksan Station ( Line 1) | 4.20 | 340.16 | Seoul-bound enter only Mokpo-bound exit only | Geumcheon | Seoul |
| | Seoul | 서울 종점 | 서울 終點 | Seobu Urban Expressway | 0.65 | 340.81 | | Geumcheon | Seoul |
| Connected directly with Seobu Urban Expressway(서부간선도로) ||||||||||

## Events

MBC's Entertainment program, Infinite Challenge held a <Seohaean Expressway Festival> in Haengdam Island Service area in June 2011.