Island Ōkunoshima before the Second World War was a place of dislocation of military spetsbazy where the experiments were conducted, and the study of chemical weapons. In particular, the mustard gas, which were officially rejected by Japan, according to the signed the Geneva Protocol of 1925. Rabbits were just those on whom the experiments were conducted. At the end of the Second World War, the base was closed, and the rabbits released. Now, on an island inhabited by a few hundred rabbits, and even a museum opened hotel.