Winter solstice, which falls on Dec 22 this year, is the day when the sun hits the Tropic of Cancer. On this day, the sun directly crosses the Tropic of Capricorn and the northern hemisphere has the shortest day and the longest night.
There was an old saying that went in ancient China, "winter solstice is as significant as the new year". Although records of people celebrating winter solstice date back to the Han Dynasty (206 BC-AD 220), celebrations really took off during the Tang (618-907) and Song (960-1279) dynasties. On this day, the imperial court had a holiday and rested. Some folks also maintained customs such as ancestor worship and family reunion. Therefore, winter solstice is also known as the "small New Year".
The poem Winter Solstice (translated by Xu Yuanchong) was written the day before winter solstice by Du Fu, a poet of Tang Dynasty. The poem says that time flies and the winter comes. Although it is freezing, the beautiful scenery into sight is embracing the next coming spring.