Gruinard Island located in Gruinard Bay, about halfway between Gairloch and Ullapool on north western coast of Scotland
It was the site of a biological warfare test by British military scientists from Porton Down in 1942, during the Second World War.
Eighty sheep were taken to the island and bombs filled with anthrax spores were exploded close to where selected groups were tethered
For many years it was judged too hazardous for the public to access to the island
In 1981 a group of activists (working under the name: Operation Dark Harvest) left a sealed package of a soil sample from the island outside the military research facility at Porton Down; tests revealed that it contained anthrax bacilli. A few days later another sealed package of soil was left in Blackpool, where the ruling Conservative Party was holding its annual conference.
Starting in 1986 a determined effort was made to decontaminate the island, with 280 tonnes of formaldehyde solution diluted in seawater being sprayed over all 196 hectares of the island and the worst-contaminated topsoil around the dispersal site being removed. On 24 April 1990, after 48 years of quarantine and 4 years after the solution being applied it was declared safe for the public.