The initial route opened in October 2011 passed through 6 stations intersecting with three existing lines at Gangnam Station ( Line 2 ) , Yangjae Station ( Line 3 ) , and Jeongja Station ( Bundang Line ) . Phase 2 opened on 30 January 2016 added 6 stations to the south , extending the line to serve Yongin 's Suji-gu and Suwon 's Gwanggyo New City . Construction for Phase 3 's extension northwards to Sinsa Station is planned in 2016 , with opening slated for 2022 . Construction started in mid-2005 , for revenue start in Sep 2011 . However , because of the flooding of late July 2011 , the opening was delayed and eventually opened on 28 October 2011
flooding of late July 2011
2011 Seoul floods
Shinbundang Line