Seoul Subway Line 9 Extension (Phase 4)

Seoul Subway Line 9 Extension (Phase 4) is a public works project supervised by the Seoul Metropolitan Government (SMG) Urban Infrastructure Headquarters to promote balanced regional development by resolving public transportation difficulties caused by local large-scale development projects, such as the construction of Godeok–Gangil Bogeumjari housing district, and improving accessibility to Gangnam.
As a civil engineering project with a total budget of ₩643.3 billion, it adds an additional 4.12 km section with four new stations and extend Line 9 subway service from the current terminal of VHS Medical Center Station to Godeok–Gangil District 1 Station (tentative name). The project kicked off in full scale after receiving approval from the Ministry of Land, Infrastructure and Transport in December, and is currently underway with the goal of completion by 2028.
When completed, Line 9 is expected to serve as a major transit thoroughfare that connects the western (Gangseo-gu) and eastern (Gangdong-gu) parts of Seoul south of the Hangang River with a total length of 45.5 km and 42 stations.

Overview

Progress Year and Contents
Category	Construction	Station (tentative)	Groundbreaking & developer
Section 1	Total 1,348 km (incl. 0.33 km tunnel) 1 station, 2 ventilations	Ecological Park Sageori Station	Dec. 30, 2021 by Daewoo E&C consortium
Section 2	Total 1,289 km (incl. 0.88 km tunnel) 2 stations, 4 ventilations	Hanyoung Foreign Language High School Station / Godeok Station	Aug. 31, 2021 by Tae Young E&C consortium
Section 3	Total 1,485 km (incl. 1.17 km tunnel) 1 station, 2 ventilations	Godeok–Gangil District 1 Station	Dec. 30, 2021 by Hanshin consortium