Choi Sun-u's Old House in Seongbuk-dong, Seoul is a museum made from the home of Hyegok Choi Sun-u, the fourth director of the National Museum of Korea. The 1930s modern hanok has a ㄱ-shaped inner wing and an ㄴ-shaped outer wing facing each other in a square layout, with a signboard reading 'Dumun Jeuk Si Sim San' above the door frame of the sarangbang. He lived here from 1976 until the end of his life, and visitors can view his belongings, works, furniture and inkstones while listening to volunteer guides, as well as the trees and plants in the back garden. It is National Trust citizen cultural heritage No. 1, purchased and preserved through citizen donations.