The“Masuya”residence was once home to a shipping agent who dealt in providing not only accommodation but also supplies for various clans at Tomonoura in the Edo Period. It is here that famous samurai Ryoma Sakamoto”stayed in hiding in the secret attic room found only after his death.

During some historical research conducted in 1989, they removed one of the ceiling boards and therefore found the hidden room. They began maintenance in 2010 and the site was open to public in 2011.

According to the document “Bingo Tomonotsu Osetsu Hikki” that describes the negotiation between Ryoma and the Kishu-han (the Kyushu clan), he had stayed there for four days starting from April 23, 1867. It also stated that he used a fake name, “Umetaro Saidani”. This was about seven months before Ryoma was assassinated in Kyoto.

Why did Ryoma come to Tomonoura? The reason is this. On April 23, 1867, Irohamaru, the ship from the Kaientai (Maritime Support Fleet) with Sakamoto Ryoma on board collided with the Kishu-han’s battleship Meikomaru near present day Mushima, in Okayama Prefecture. The crew of the Irohamaru transferred to Meikomaru, and tried to tow the heavily damaged Irohamaru towards Tomonoura but the Irohamaru sank on the way to the port.

During the incident, Kaientai members lodged at Masuya Seiemon Taku (residence), while the Kishu-han’s people were at Enpuku-ji Temple. Even though they had tried for four days to negotiate a way to solve the issue of the accidental sunken battleship at the residence of Uoya Manzo and Taichoro of Fukuzen-ji Temple, Kishu-han decided to flee from Nagasaki, leaving the Irohmaru crew stuck. Ryoma’s members turned on him and began to blame him for what had happened.

This “Irohamaru incident” marked the first time steamboats had collided in Japan, as well as the first marine accident inquiry under international law.


Ryoma’s hideout in Masuya Seiemon’s residence
Address/ 422 Tomo, Tomo-cho, Fukuyama-shi, Hiroshima
Tel/ +81-84-982-3788
Opem/ 9:00〜16:30 on Monday, Friday, Saturday, Sunday, National holidays
Admission fee/ 200 yen for adult, 100 yen for student under high school student
https://www.masuya-seiemontaku.com