Ssangmun-dong (Korean: 쌍문동) is a dong (neighborhood) of Dobong District, Seoul, South Korea.

[1][2] The name of the neighbourhood literally means two doors and originated from the fact the region used to have two yeolnyeomun—a special door awarded to a yeolnyeo (or "virtuous woman").

[3] The location has been used in many South Korean shows because the area was once home to a lot of old buildings and alleyways, and is characterised as a place where rather impoverished people live.

This makes it easier for writers to establish "rags to riches" stories and to communicate a sense of warmth to the audience and a place with nostalgic quality.

[4] The location was popularized internationally by the 2015 Korean drama Reply 1988 and the 2021 Netflix hit series Squid Game, where it was the home of Seong Gi-hun and his childhood friend Cho Sang-woo.