The south wall refers to the shadow wall, which is used to block the view in traditional buildings in China. Generally speaking, the gates of buildings in China face south. In the past, influential people had shadow walls outside their gates, so when they left the gates, they had to go left or right. If they go straight, they will definitely hit the south wall!
detailed description
Most of the ancient houses face south, and there is a wall in the entrance, which is called "zhaobi" or "yingbi", which can block the eyes of outsiders and the straight airflow.
This wall is the "South Wall". When you come out of the main entrance, you must avoid it and walk around, or you will bump into it. For various reasons, the South Wall has become an indispensable part of the ancient buildings in China. The south wall and the houses, gates, aisles and walls of the inner courtyard form a whole.