Only after World War II did the secret spill: Ōkunoshima, located in the Inland Sea of Japan between Hiroshima and Shikoku, was the top-secret site for manufacturing chemical warfare. When the factories were closed down, a number of exotic wild rabbits were seen freely roaming the island. They were assumed to have been the test subjects for the chemical weapons, which the military failed to eradicate when the factory was demolished.

Paint splattered police officers look on during clashes outside Top Shop on Oxford Street, during marches in protest at government cuts on March 26, 2011 in London, England. Thousands are taking part in the Trades Union Congress (TUC) organised march to Hyde Park where a rally will take place. Police say they are deploying 4500 officers. (Photo by Dan Kitwood/Getty Images)

The sun shines on Weston-super-Mare's Sand Sculpture Festival and the sand art currently being displayed on July 4, 2011 in Weston-Super-Mare, England. Now in its fourth year and with a Amazon Jungle theme for 2011, the seaside resort's event attracts top sand sculptors from across the world and runs throughout the summer months. (Photo by Matt Cardy/Getty Images)

Shannon McGurgan (Bottom), Farhad Ahadi (Middle) and Malia Walsh (Top) perform the Circus Trick Tease on stage at a media call ahead of the inaugural Melbourne Circus Festival on September 23, 2011 in Melbourne, Australia. The National Institute of Circus Arts will showcase artists from around the world during the first ever circus festival in Melbourne from September 26 – October 2. (Photo by Hamish Blair/Getty Images)

The extravagant residence Castello di Sammezzano sits on top of a hill in Tuscany, Northern Italy. Originally it was built in the Moorish style in 1605 for Ximenes d'Aragona and then re-designed between 1853 and 1889. After the war the castello was used as a luxury hotel until closure in the mid to late 1990's. It was abandoned until April 2012 when the FPXA committee was formed, aiming to promote and enhance the castle.

A great tit eats food from the top of a photographer's hat as the press wait for politicians on Downing Street on December 16, 2019 in London, England. The UK's Prime Minister is set to hold a mini Cabinet reshuffle to replace outgoing ministers following last week's general election victory. (Photo by Leon Neal/Getty Images)

A groundskeeper uses a bamboo broom at Kasumigaike Pond at Kenrokuen Garden in Kanazawa, Japan on January 12, 2016. The japanese garden, located next to Kanazawa Castle, encompasses over 28 acres in downtown Kanazawa. With two ponds, rolling hills with streams and bridges, is considered a strolling-style landscape garden. It's regarded as one of the top three most beautiful gardens in Japan. (Photo by Linda Davidson/The Washington Post)

Attendants prepare to fill glasses for delegates before the opening session of the Chinese People's Political Consultative Conference at Beijing's Great Hall of the People, Thursday, March 3, 2016. The more than 2,000 members of China's top legislative advisory body convened their annual meeting Thursday, kicking off a political high season that will continue with the opening of the national congress on Saturday. (Photo by Mark Schiefelbein/AP Photo)