The collection focuses on the history and folkways of Shimonoseki and its environs, and includes the Kofun period Prefectural Tangible Cultural Property "Excavated Artefacts from Shinkōji Kofun", Nara period Important Cultural Property "Nagato Province Coin Remains", roof tiles from Nagato Kokubun-ji, the and Ōuchi clan administrative documents known as , both Prefectural Tangible Cultural Properties, and materials relating to the Joseon missions to Japan, Tagami Kikusha, Sakamoto Ryōma, Takasugi Shinsaku, the "Kiheitai", and the Shimonoseki campaign and Chōshū expeditions.