Tomb-Sweeping Day is an ancient festival of the Chinese nation. It is not only a solemn festival to pay homage to ancestors, but also a happy festival for people to get close to nature, have an outing and enjoy the fun of spring. Douzhi B (or solar calendar reaches 15) is Tomb-Sweeping Day gas, and the node time is around April 5 of Gregorian calendar. At this time, Yin Qi is full of vitality, and everything is "going to the old and welcoming the new", and the earth presents a scene of spring, tranquility and peace.

This is a good time for a spring outing and Qingming ceremony in the suburbs. Tomb-Sweeping Day, who worships his ancestors, is very long. There are two statements: 8 days before 10 and 10 days before 10. These nearly 20 days belong to Tomb-Sweeping Day who worships his ancestors.

According to documents, some places in northern China had a strict fire ban system in the pre-Qin period, and there was a custom that officials changed fire to serve the people. Zhou Li, written in the Han Dynasty, clearly recorded that there was an official who was a torchbearer at that time. Whenever the climate in mid-spring is dry, not only the kindling preserved by human beings is easy to cause fire, but also the occurrence of spring thunder is easy to cause mountain fires.

In this season, the ancients often held grand sacrificial activities to put out all the fires handed down from the previous year, that is, "no fire."