Ōkunoshima is a small island in Japan's Seto Inland Sea where hundreds of wild rabbits come bounding out of the bushes to greet every ferry. Nicknamed Rabbit Island, it is one of the gentlest day trips in western Japan, and it also holds one of the darkest chapters of the country's 20th-century history: a secret poison gas factory.

Hand offering food to a rabbit on the grass on Ōkunoshima, with the sea and hills behind
Feeding a rabbit on Ōkunoshima. Photo: ZyklusDieWelt / Reddit.

Ōkunoshima, Rabbit Island in Hiroshima Prefecture

The island belongs to the city of Takehara in Hiroshima Prefecture and lies just off the mainland coast near the port of Tadanoumi. A road and a seafront path run around the small island, so it is easy to explore on foot or by bicycle.

The rabbits are the star. Nobody knows exactly how many there are, but estimates run into the thousands, and with no natural predators, no hunting and no cats or dogs allowed on the island, they have thrived. Nearly 200,000 people visited in 2024.

Tawny rabbit lying on gravel in front of a building on Ōkunoshima
Brown rabbit eating a cabbage leaf on Ōkunoshima
Three rabbits looking straight at the camera on Ōkunoshima
Two rabbits in low evening sunlight on Ōkunoshima, Rabbit Island

A cycling couple's night with the rabbits

The photos here come from Reddit user ZyklusDieWelt, who spent a night camping on the island with a girlfriend during a cycling tour of Japan in 2014. Their loaded touring bike appears in a few frames, but the pictures are mostly rabbits: lounging in the sun, nibbling cabbage, and gathering in crowds of a dozen or more around anyone who crouches down with a bag of food.

Woman sitting on the pavement feeding a group of rabbits on Ōkunoshima
Loaded touring bicycle on the seafront path of Ōkunoshima with a rabbit nearby
Large brown rabbit grooming on a stone path on Ōkunoshima
Smiling woman holding out food to a rabbit beside a fence on Ōkunoshima
Rabbits on a sandy shore of Ōkunoshima with the Seto Inland Sea beyond
Woman crouching on sand surrounded by feeding rabbits on Ōkunoshima
Huddle of brown and black rabbits on sandy ground, Ōkunoshima

Where the rabbits came from

The origin of the rabbits is a matter of local debate. The best-supported account is that they descend from rabbits released after the Second World War, when the island was redeveloped as a park, and from a group set free by schoolchildren in the early 1970s; one version puts it at eight rabbits in 1971.

A darker story links them to the roughly 200 rabbits used in wartime gas experiments. Those animals were put down when the factory was demolished, and scientists consider a genetic link to today's rabbits very unlikely.

Rabbits of many colours, including a white one, crowding around a visitor's feet
Dozens of rabbits spread across a car park on Ōkunoshima
Visitors and rabbits on an open field on Ōkunoshima – photograph by ZyklusDieWelt

The poison gas island

Between 1927 and 1929 the Imperial Japanese Army built a chemical weapons plant on Ōkunoshima. Over the following years it produced more than six kilotons of mustard gas and tear gas. The project was so secret that the island was removed from some maps, and many of the workers and local people were never told what was being made there.

Today the small Ōkunoshima Poison Gas Museum, opened in 1988, tells that story. Around the island you can still see the concrete ruins of the wartime plant, along with forts built during the Russo-Japanese War. Many ruins are fenced off and unstable, so stay on the marked paths.

Woman crouching with a food bag as a crowd of rabbits gathers on Ōkunoshima
Rabbits gathering around a crouching visitor by a shelter on Ōkunoshima
Dense crowd of brown, grey and white rabbits on tarmac on Ōkunoshima

How to visit Ōkunoshima

  • Getting there: take the JR Kure Line to Tadanoumi Station, walk to the nearby port and catch the ferry across. Ferries also run from Ōmishima island.
  • Staying: the island has a resort hotel, Kyukamura Ohkunoshima, and campgrounds.
  • Feeding: Japan's national tourism organisation encourages visitors to bring or buy rabbit food. Be ready to move on when your bag is empty, because the rabbits will follow you.
  • Good manners: let the rabbits come to you, and do not pick them up or chase them.
  • Combine it: Ōkunoshima pairs well with a day in Hiroshima city.
Close-up of a rabbit on the grass with a touring bicycle behind, Ōkunoshima

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