The event of Ghadir Khumm (; ) refers to a sermon delivered by the Islamic prophet Muhammad at the Pond of Khumm (), shortly before his death in 632 CE. According to Shi'ite traditions, in the sermon Muhammad announced Ali ibn Abi Talib as his successor, after which the final verse of the Quran was revealed, proclaiming the perfection of the religion of Islam. The day's anniversary in the Islamic calendar (18 Dhu al-Hijjah) is celebrated by Shi'ite Muslims as Eid al-Ghadir.