Celebrated on the longest night of the year, Dong Zhi is the day when sunshine is weakest and daylight shortest. The coming of winter is celebrated by families and is traditionally the time when farmers and fishermen gather food in preparation for the coming cold season. It is also a time for family reunions.

This celebration can be traced to the Chinese belief in yin and yang, which represent balance and harmony in life. It is believed that the yin qualities of darkness and cold are at their most powerful at this time, but it is also the turning point, giving way to the light and warmth of yang. For this reason, the Dong Zhi Festival is a time for optimism.