| Sarushima | |
| Native Name: | 猿島 |
| Sobriquet: | Monkey Island |
| Image Alt: | The island of Sarushima is golden on a late August day. In the lower right corner a few men on the deck of a boat look back at the island |
| Pushpin Map: | Japan Tokyo Bay and Boso Peninsula#Japan Kanagawa Prefecture |
| Location: | Yokosuka, Kanagawa |
| Coordinates: | 35.2861°N 139.6942°W |
| Area Km2: | 0.055 |
| Coastline Km: | 1.6 |
| Elevation M: | 39.3 |
| Country: | Japan |
, is a small island located off Yokosuka, Kanagawa in Japan. It is the only natural island in Tokyo Bay. Sarushima was used as a battery by the Tokugawa shogunate during the Edo period, and after the Meiji Restoration in 1868, the island was developed as part of the Yokosuka Navy Yard.[1] [2]
Matthew C. Perry named the island Perry Island in 1853.[3]
Sarushima is now uninhabited, and after World War II, it was developed as a marine park. Swimming and camping facilities were built on Sarushima, which makes it a popular fishing spot. The highest part of the island is still surrounded by a stone wall from the pre-war period, and features the remains of red brick barracks and a powder magazine. The island is accessible by a ferry.