Seoul Metro Corporation () was a municipal-owned corporation owned by the Seoul Metropolitan Government. Established in 1970, it was, with Seoul Metropolitan Rapid Transit Corporation and Korail, one of the major operators of Seoul Metropolitan Subway. The company merged with Seoul Metropolitan Rapid Transit Corporation in 2017. History June 8, 1970: Subway construction headquarters April 1971: Line 1 (Cheongnyangni Station - Seoul Station) construction started and opened October 1974: Gunja Depot construction March 9, 1978: Line 2 Gangnam Section construction started February 29, 1980: Line 3 and 4 construction started May 22, 1984: Line 2 Circle Line opened October 18, 1985: Line 3 and 4 opened July 13, 1990: Line 3 (Gupabal Station - Jichuk Station) opened May 22, 1992: Line 2 Sinjeong Branch (Sindorim Station - Yangcheon-gu Office Station) opened April 21, 1993: Line 4 (Sanggye Station - Danggogae Station) opened October 10, 1993: Line 3 (Yangjae Station - Suseo Station) opened April 1, 1994: Line 4 (Sadang Station - Namtaeryeong Station) opened March 20, 1996, Line 2 Sinjeong Branch (Sinjeongnegeori Station - Kkachisan Station) opened October 20, 2005: Line 2 Yongdu Station opened December 21, 2005: Line 1 Dongmyo Station opened February 18, 2010: Line 3 (Suseo Station - Ogeum Station) opened March 28, 2015: Line 9 (Eonju Station - Sports Complex Station) opened May 31, 2017: Merged with Seoul Metropolitan Rapid Transit Corporation & Seoul Metro Lines Seoul Metro's service covers a part of Seoul Subway Line 1, and the whole Seoul Subway Line 2, Seoul Subway Line 3, Seoul Subway Line 4. For lines 1, 3, and 4, Korail jointly participates in the service. Seoul Metro controls the railways and stations which are owned by Seoul Metropolitan Government. Line 1 Control: Cheongnyangni station - Seoul Station Service: Yangju station - Incheon station / Seodongtan station Total Length: 7.8 km Line 2 Circle Line: City Hall station ↔ Seongsu station ↔ Gangnam station ↔ Sindorim station ↔ Hongik University station ↔ City Hall station Seongsu Branch Sinjeong Branch (Except for Kkachisan station controlled by Seoul Metropolitan Rapid Transit Corporation) Total Length: 60.2 km Line 3 Control: Jichuk station - Ogeum station (Except for Garak Market station controlled by Seoul Metropolitan Rapid Transit Corporation) Service: Daehwa station - Ogeum station Total Length: 38.2 km Line 4 Control: Danggogae station - Namtaeryeong station Service: Danggogae station - Oido station Total Length: 31.7 km Line 5 Control: Ogeum station Line