Eid El Kbeer (Eid El Adha) marks the high point of the Muslim year with the commemoration of Abraham's near sacrifice of Ishmael before God intervened and commended him to sacrifice a ram instead. (Yes, I am aware that the Biblical version is slightly different.) In commemoration of the event, Muslims throughout the world sacrifice a sheep on this day.
To all my Muslim and Moroccan friends, happy Feast of the Sacrifice!