The Dangsan Railway Bridge (Hanja: 堂山鐵橋) crosses the Han River in Seoul. It is used exclusively by Seoul Metro Line 2, connecting from Station 238: Hapjeong Station, Hapjeong-dong, Seoul Mapo-gu to Station 237: Dangsan Station, Dangsan-dong 6-ga, Seoul Yeongdeungpo-gu. Immediately on the south side of the bridge is Dangsan Station, which is on an elevated platform. Hapjeong Station, a subterranean station in Seoul Mapo-gu, is located approximately 600 meters north of where the bridge makes landfall.
After the partial collapse of Seongsu Bridge in 1994, every bridge in Seoul was re-examined for safety and it was decided that Dangsan Bridge should be taken down and rebuilt. Amid considerable controversy, this bridge was closed for reconstruction on December 31, 1996. The reconstruction finished on November 22, 1999.