Ryosenji Temple is modest in scale, but it matters more than it looks. In 1854, officials of the Tokugawa shogunate and Commodore Perry signed the Treaty of Shimoda here, opening Shimoda and Hakodate to American ships.
The temple museum keeps material connected with Perry, the Black Ships, and early contact between Japan and the United States. Come after walking Perry Road; the treaty history lands better when you have already seen the harbour and the old streets around it.