British engineering and design consultancy Arup has signed a contract with Shanghai Industrial Investment Corporation (SIIC) to plan the world’s first sustainable “eco-city” – at Dongtan, outside of Shanghai. The new city, which will be three-quarters the size of Manhattan, will be built on the eastern end of Chongming, a large island that sits in the mouth of the Yangtze river delta a few miles northeast of the city centre, close to Shanghai’s new airport.