Shiun Maru disaster

The Siun Maru disaster (紫雲丸事故 Shiun Maru Jiko) was a ship collision in Japan on 11 May 1955, during a school field trip, killing 168 people.

The Shiun Maru ferry sank in the Seto Inland Sea after colliding with another Japanese National Railways (JNR) ferry, the Uko Maru, in thick fog. A lack of radar onboard contributed to the accident. The victims included 100 students from elementary and junior high schools in Shimane, Hiroshima, Ehime and Kochi prefectures who were on school trips. The sinking of the Siun Maru is credited as having encouraged the Japanese government to go ahead with the Akashi Kaikyō Bridge project, the longest suspension bridge in the world.