Photos

This was taken at Seodaemun Prison. This is a shot through a slot in one of the cell doors, presuamably where the food was passed through.

From wikipedia:
Seodaemun Prison is a museum and former prison in Seodaemun-gu, Seoul, South Korea. It was constructed beginning in 1907 while Korea was considered a protectorate of Japan. The prison was opened on October 21, 1908, under the name Gyeongseong Gamok. Its name was changed to Seodaemun Prison in 1923.

The prison was used during the Japanese rule of Korea to house anti-colonial activists, and could accommodate around 500 people. After the Japanese occupation ended in 1945, the prison was used by the South Korean government until 1987, when it was replaced by a facility in Uiwang City, Gyeonggi Province. In 1992, the site was dedicated as the Seodaemun Prison History Hall, part of Independence Park. Seven of the prison complex's original fifteen buildings are preserved as historical monuments