City wall in Jingzhou city, Hubei Province (Photo/Chinanews.com)
The study of these ancient walls have allowed experts to decipher traditional Chinese cultures and history.
"For instance, the city wall of Nanjing. Nanjing's city walls were not built following the traditional shape of a square. Instead, it was built in accordance with astronomy," said Yang.
"Originally, the ancient Nanjing city wall had 13 gates, each representing a constellation. The main palace was located at the center of the Plough, and that is why the rulers at that time preferred to fill the lake to build the palaces," said Yang.
According to Yang, Nanjing's city wall is a mixture of Taoism which was just taking off at the beginning of the Ming Dynasty (1368-1644) and the special geographic location of the city.
