Where is the license plate number starting with 'Ao' from?

[SanCaden]

Currently, there is no license plate number starting with 'Ao'. The first Chinese character at the beginning of a license plate represents a province or municipality directly under the central government, and the letter following the first character represents a city or district. By looking at the first Chinese character and the letter on the license plate, you can determine where the vehicle belongs. A license plate is a mandatory requirement for every car to legally operate on the road. License plates can be either official or temporary. Temporary license plates are made of paper and do not need to be fixed to the front or rear of the vehicle body. However, temporary license plates must be affixed to the inside of the front and rear windshields. If they are not affixed as required, it is equivalent to driving without a license plate. Temporary license plates have a validity period, and if they expire, they should not be used for continued driving, otherwise it is also considered as driving without a license plate.