DOSSIER - San Francisco: at the roots of tomorrow's world

San Francisco, with just 850,000 inhabitants, is a real powerhouse. An ecological power, since the Californian metropolis manages to reuse 80% of its waste, and is aiming for "zero waste" by 2020. It is also an economic power, with its city centre increasingly sought after by major groups and start-ups. At the same time, this is helping to relieve some of the pressure on Silicon Valley, whose dazzling success has led to soaring property prices in the region. The Bay Area is rich and innovative, but it's also beautiful. And very close to nature. Organic farms supply alternative restaurants and cafés, and hotels are going green. Green, but above all in the spirit it conveys. A very unexpected "flower power". Report Cécile Balavoine -Photos Ludovic Maisant