A cluster of world-class cities for work, life and leisure forms the central vision of the “Greater Bay Area” finally unveiled by the Chinese government late on Monday, laying out a road map to what it hailed as the new era of opening up. Coming 40 years after the 1978 opening up of China, the State Council published a document setting out an ambitious plan to transform 11 cities around the Pearl River Delta into a thriving global centre of technology, innovation and economic vibrancy.