Line 3 (Suyeong(수영)~Daejeo(대저)) started its service in 2005. It is aimed at reducing traffic in Mandeok(만덕), Minam(미남) and Yeonsan-dong(연산동). Line 3 also connects relatively isolated Gangseo(강서) area with the center of the city. It is expected to help to improve the quality of life in Gangseo(강서) region. Line 3 is 18.1 km long with 17 stations. It is middle-sized subway and uses a 4-cars train. Line 3 subway is a Korean standard type train. All equipment is localized, and a train itself is 20% lighter than line 1 subway.