The Death of Prophet Zarathustra remembers the death of Zarathustra (also called Zoroaster), the prophet whose teachings are the foundation of Zoroastrianism. It is observed with prayers, visits to fire temples, and reflection on his ethic of good thoughts, good words, and good deeds. The Fasli calendar places it on December 26, and communities following the Shahenshahi or Kadmi calendars observe it on different dates.