日露和親条約
On December 23, 1854, "Diana", the flagship of the Russian fleet bearing Admiral Yevfimy Putyatin and his delegation for the negotiation of the Treaty of Shimoda was struck by a tsunami from the Ansei Tōkai earthquake and sank. The survivors stayed in Heda, where they cooperated with Japanese carpenters and shipbuilders to construct a new vessel (christened "Heda") to take them back to Russia. This marked the first cooperative venture between Japanese and Europeans since the start of the national seclusion policy at the start of the Edo period.