The timing of caravans was governed by the availability of water and pasture or, in the case of the Muslim pilgrim caravans, by the need to be in Mecca on the 8th day of the month of Dhū al-Ḥijjah. Consequently the Orenburg caravan left Bukhara after the melting of the Russian winter snows, and the Basra caravan left Aleppo after the Middle Eastern rains of late autumn.