Transportation experts say there's barely enough space on the roads in China's largest cities for the 35 million cars that were bought during the past decade of frenzied consumerism. Photo: Remko TanisThis piece was written by Melinda Burns. The new Great Wall of China is the "Great Wall" of cars stuck in city traffic, researchers say, and it will take more than restrictions on new license plates and car registrations to break the gridlock. The problem is, there's barely enough space on the roads in China's largest cities for the 35 million cars that were bought during the past decade …