Winter Solstice (English: winter?solstice), also known as "Winter Festival" and "Winter Festival", is one of the twenty-four Chinese solar terms and one of the eight astronomical solar terms, opposite to the summer solstice. The winter solstice begins when the sun reaches 270° of ecliptic longitude, which is around December 22 of the Gregorian calendar every year. It is said that the winter solstice was the New Year's Day in the Zhou Dynasty in history, and it used to be a very lively day. The winter solstice usually falls on December 21st or December 22nd in the Gregorian calendar. Because the Winter Solstice is not fixed on a specific day, it is called a "living festival" just like Qingming Festival.

On the winter solstice, the sun reaches the southernmost point of the year, almost directly hitting the Tropic of Capricorn (23°26' south latitude). The northern hemisphere gets the least sunlight on this day, 50% less than the southern hemisphere. The days in the Northern Hemisphere are at their shortest, and the days get shorter as you go further north.

It is more common in northern China to have the custom of eating dumplings during the Winter Solstice. As the saying goes: "When the winter solstice comes, eat dumplings." In the south, people eat dumplings. Of course, there are exceptions. For example, in places such as Tengzhou, Shandong, the custom of counting nine during the winter solstice was popular. The custom of drinking mutton soup on the day of the count nine was popular, which meant to drive away the cold. .

In astronomy, the winter solstice is regarded as the beginning of winter, which is obviously too late for most areas in our country. During the winter solstice, the average temperature in the northwest plateau is generally below 0°C, while in the south it is only around 6°C to 8°C. However, in the low-altitude valley areas in the southwest, even in early January, the coldest time in the area, the average temperature is still above 10°C. It can be said that autumn has passed and spring has calmed down, and there is no winter all year round.