Q:When I walk through Beijing's hutongs, I try to look into the open doors to get a glimpse of life in the courtyard houses. But often there are walls blocking the view! Can you tell me the purpose of these walls?
A:Screen walls, or spirit walls, are a common feature of the courtyard-style houses that line the hutongs of Beijing and other cities. One of their original functions was to frustrate nosey passers-by and allow people in the courtyards a little privacy. Another, no less important function of these walls was to frustrate something far more insidious: evil spirits. According to Chinese superstition, malevolent ghosts and devils can only move in straight lines. Thus a wall built just inside the door of a home would keep out any unwanted otherworldly visitors while presenting only a minor inconvenience to the living inhabitants, who could simply walk around it.
Naturally, more important households or temples required larger, more elaborate spirit walls. The most impressive version is the Nine-Dragon Screen (jiu longbi), a massive barrier decorated with protective dragons crafted from colorful, glazed tiles. There are three such walls in China. Beijing features two: one in Beihai Park, and one in the Imperial Palace.
Surprisingly, the largest Nine-Dragon Screen is not in the Forbidden City, but in Datong, Shanxi province. Now about 600 years old, the 45m long, 8m high wall once guarded the home of the thirteenth son of Hongwu, the first Ming emperor.