City Moat

There is always a ditch running parallel with and out of the city wall, which is referred as the city moat in ancient times. In the cold weapon era, the city moat is the best defense line, and also the major source to supply city-building materials. The archaeological drilling suggests that the original moat was around 20 meters wide and over 4 meters deep. However, its most part has silt up now, with only the section in the west of city remaining navigable.