Eighth Oka feudal lord Nakagawa Hisasada invited Confucianist Karahashi Kunzan to Oka feudal clan from Edo. Kunzan imitated a tower gate of the Kanzan temple at Suzhou in China and built it. Bungokokushi, 'History of Oita' was edited by the command of the Shogunate at this building, but it had not been completed because Kunzan died from disease. Thereby, Tanomura Chikuden and Ito Kyoga took this over. It was begun in 1798 and concluded in 1803.