Ōkunoshima

Ōkunoshima (大久野島^?) is a small island located in the Inland Sea of Japan in the city of Takehara, Hiroshima Prefecture. It is accessible by ferry from Tadanoumi and Ōmishima. There are campsites, walking trails and places of historical interest on the island. It is often called Usagi Shima (うさぎ島^?, "Rabbit Island") because of the numerous feral rabbits that roam the island; they are rather tame and will approach humans.

Ōkunoshima played a key role during World War II as a poison gas factory for much of the chemical warfare that was carried out in China.

The island was a cultivated area until the Russo-Japanese War when ten forts were built to protect it. Three fishing families lived on the island.

In 1925, the Imperial Japanese Army Institute of Science and Technology initiated a secret program to develop chemical weapons, based on extensive research that showed that chemical weapons were being produced throughout the United States and Europe. Japan was a signatory on the 1925 which banned the use of chemical warfare. Although the development and storage of chemical weapons were not banned, Japan went to great lengths to ensure the secrecy of construction of the chemical munitions plant begun in 1929, even going so far as to remove records of the island from some maps. The plant was built over the period of 1927 to 1929, and was home to a chemical weapon facility that produced over six kilotons of mustard gas and tear gas.

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