Festivals, in which worship is an essential part, are characteristic aspects of Zoroastrianism. The principal festivals in the Parsi year are the six seasonal festivals, Gahanbars, and the days in memory of the dead at year's end.
Also, each day of the month and each of the 12 months of the year is dedicated to a deity. The day named after the month is the great feast day of that particular deity.
The New Year festival, Noruz, is a joyous spring festival in honour of Rapithwin, the personification of noonday and summer. The festival to Mithra, or Mehragan, was traditionally an autumn one.