Do you know which two cities across the country have Huabiao?

Huabiao originated very early. As early as the era of Yao and Shun, emperors were accustomed to setting up wooden pillars at various traffic arteries and intersections. According to "Huainanzi", this kind of pillar is "the tree of Shun's slander" and "the wood of Huabiao that writes his good and evil". It means that if the people have any criticisms and suggestions for the emperor, they can be written on these wooden pillars called Huabiao. It can be seen that Huabiao was originally a tool to promote democracy. During the Qin Shihuang era, Huabiao was abolished in order to strengthen autocratic rule. In the Han Dynasty, Huabiao was restored and called "Huan Biao". However, because the feudal emperors did not like to listen to criticism and did not allow people to express their opinions, Huabiao gradually became a road sign at the center of the street, and later it became a stone carving art and used as a decoration for buildings.

In addition to a pair of Chinese watches on the front and back of Tiananmen Square, there are also Chinese watches carved from white marble in Beijing Library, the campus of Peking University, and inside the Dahongmen of the Ming Tombs. There is a sitting beast on the top of the Huabiao, which looks like a dog but not a dog. It is called Roar. It is a carnivorous beast. Have you ever noticed that the flowers on the top of the pair of Chinese watches in front of Tiananmen face south, while the flowers on the top of the pair of Chinese watches behind Tiananmen face north. What's the significance of this? It is said that the one facing north is called "Wang Jun Chu", which means to remind the emperor not to indulge in palace life, and should often go out and experience the sufferings of the people. The one facing south is called "Wang Jun Return", which means to remind the emperor not to indulge in palace life for too long. When you are wandering around and forget about state affairs, you should return to the palace to handle the affairs of the state. In fact, these symbolic meanings only reflect the people's wishes and expectations for the rulers.

In all dynasties and generations, which emperor's whereabouts were truly controlled by "Huabiao"?