Devil's Island
Also Known As: Ile du Diable 27.5 °C 
There are a lot of (former) prison islands on earth, but none with a reputation so notorious as Ile du Diable or Devil's Island. Together with Isle Royale and Isle St. Joseph it forms Iles du Salut and the three of them served as a penal colony, created under Napoleon III and gladly upheld as such by the Emperors predecessors. At least 80,000 people were sent here from France. And all but a meagre 2,000 of them perished here. That explains its nickname - although the official name serves it all up pretty good - “Dry Guillotine”: this was a place where people were sent to die in a slow and agonising way.
A lot of criminals but also a lot political opponents that those in power back in France wanted to get rid off.
By far the most famous was Alfred Dreyfus, a captain in the French army who was falsely accused and convicted of treason. It was only after French intellectuals, after learning the truth about this case, made a huge uproar. The famous open letter 'J'accuse...!' by writer Emile Zola made it into an international affair that embarrassed the authorities in Paris. Dreyffus was released are more than four years in this living hell.
Another famous story is that of inmate Henri Charrière. He was one of the few to actually escape from the island. He wrote a very successful book about it: Papillon. The story later turned into a blockbuster Hollywood movie with Steve McQueen and Dustin Hoffman in the leading roles.
After the Second World War the prison island was shut down and slowy overtaken by the jungle. The car train that gave access to Devils Island from nearby Isle Royale broke down and ever since it is hardly possible to get to the island. Apart from the ruins of the prison buildings the only thing to be found on the island is measuring equipment for the space center that France has on the mainland of French Guiana.