Wild ducks foraged and flew in the ice-covered wetlands during Sijiu, the fourth nine days after the Winter Solstice, in Qinhuangdao City, north China's Hebei Province, adding life to the cold winter. 

Sijiu is a folk solar term in addition to the traditional Chinese 24 solar terms, which follows the end of Sanjiu, the third nine days after the Winter Solstice. 

Sijiu and Sanjiu represent the coldest period of the year. This year, Sijiu falls on January 17.

(All images via VCG)

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