The birth anniversary of Prophet Spitaman Zarathusatra (Zoroaster), who founded Zoroastrianism, is celebrated as Khordad Sal. It falls sometime in August or September, on the sixth day of the Parsi month of Farvardin.

The exact year of Zarathushtra's birth is not known, but it is generally accepted that he was born in the beginning of the first millennium BC.

Similarly, the day of his birth is also not precisely known, and the fixing of Khordad Sal as his birthday is symbolical.The religious lore and texts of the Parsis mention the festival and its importance. In some old Parsi texts, this day is also spoken of as the Navroz-I-Khas, which means 'special new year's day', while the real New Year's day is referred to as Navroz-I-Am, meaning 'common new year's day'.

In the olden days, the king and nobility, especially, observed Khordad Sal as Navroz-I-Khas. It is said to be the day on which many historic events of old Iran are said to have happened. Later, it came to be observed solely as Zarathushtra's birthday. Rituals

Clean, rangoli-strewn homes, children with vermilion spots on their foreheads, new clothes, fragrant flowers and delicious meals, all form part of the rituals. Jashan, or thanksgiving prayers, are offered to God in the agiaries. A grand feast is prepared to mark the occasion.

Since the Parsi community is especially tight-knit, its celebrations bring kith and kin together; so does Khordad Sal. The festival is also an opportunity for the Parsis to review their lives and actions, and make resolutions for the future.