the cold food festival was originally observed at mid-winter (the dongzhi solar term), but moved to late spring (the qingming solar term) around the 2nd century. its primary activity was a strict taboo against using fire, usually under the superstitious belief that violations led to violent weather. leading up to the 6th century, there was a patch of blackened trees on that were used for local worship of jie zhitui and had a reputation for miracles. traditional cold foods included "lǐlào" , a kind of congee flavored with apricot pits and malt sugar. later activities included visiting ancestral tombs, cock fighting, playing on swings, beating blankets, and tug-of-war games.