The small island of Ōkunoshima (大久野島) in the Inland Sea of Japan is famous for two things: poison gas and bunnies. In 1925, the Imperial Japanese Army started a secret program to develop chemical weapons in defiance of the Geneva Protocol. They built a gas plant on the island four years later that made mustard gas. Ōkunoshima was chosen for its isolation and to keep the plant secret the island was even removed from some maps.
After the war, the poison was disposed of and the laboratory animals—rabbits—were set loose. Without any predators on the island, the bunny population exploded, and now the island is full of tame rabbits that visiting Instagrammers have captured with videos and photos.