Eid Adha, also called the "Festival of the Sacrifice", is the second of two Islamic holidays celebrated in Xinjiang and the world each year, the other being Eid al-Fitr, and considered the holier of the two.
The festival was set to honor Abraham who sacrificed his son as an act of obedience to God's command. In the story, before Abraham could sacrifice his son, however, God provided a lamb to sacrifice instead. In commemoration of this, an animal is sacrificed at the festival and divided into three parts: one is given to the poor and needy; second part is for the home, third is given to relatives.
In the Islamic lunar calendar, Eid Adha falls on the 10th day of Dhu al-Hijjah. In the international calendar, the dates vary from year to year drifting approximately 11 days earlier each year.
During the day, men, women, and children are expected to dress in their finest clothing to perform Eid prayer in a large congregation in an open field called Eidgah or mosque. Affluent Muslims who can afford it will sacrifice their finest domestic animals as a symbol of Abraham's willingness to sacrifice his only son to God.