On the island of Rügen in the Baltic Sea lies one of the most megalomaniac projects built by the Nazis. The ‘Monster by the Sea’, a colossus of brickwork that stretches for kilometres, intended as a futurist holiday resort for the inhabitants of the Third Reich. A paragon of ‘guilty architecture’. Later occupied by the communist regime, it has since the fall of the Wall fallen victim to property developers who have found it a tough nut to crack. Nico Weber’s Inside Prora uncovers the storied history of a project that symbolises the utopian intentions of modernism and the emergence of mass tourism.