According to the Shenzhen traffic management department, the total number of cars in Shenzhen reached 1.7 million on December 8th, 2010. Shenzhen has become the number one city in China with high car density. The Shenzhen traffic management department estimates that Shenzhen’s maximum volume of motor vehicles will be 2.1 million according to the present number of roads in the city. That is to say that it is estimated that Shenzhen’s car number will reach its limitation in the next two years and it will be very difficult to drive.