Tafilalt or Tafilet (Berber: Tafilalt, ⵜⴰⴼⵉⵍⴰⵍⵜ; ) is a region and the most important oasis of the Moroccan part of the Sahara Desert; it is also considered one of the largest oases in the world. Entirely located along the Ziz River, the oasis ten days' journey south of Fez, across the Atlas Mountains. It is celebrated for its large and luscious dates. Al Hassan Addakhil, ancestor of the reigning Alaouite Dynasty of Morocco, cultivated these with such success around 1250 that he could fund the dynasty's rise to power.