What is Sizdah Bedar?

Sizdah Bedar also known as Nature's Day is an Iranian festival held annually on the thirteenth day of Farvardin, the first month of the Iranian calendar (and the first month of spring, during which people spend time picnicking outdoors. It marks the end of the Nowruz holidays in Iran.

Generally, among Iranian festivals, "Sizdah Bedar" is a bit vague in terms of historical roots. There is no direct mention of such a celebration in history books prior to Qajar era. But in ancient sources, such as Shahnameh, there is a reference to "the thirteenth day of Farvardin". The popular belief is that ancient Iranians celebrated the 13th day of Nowruz after twelve days of celebrating, each day represents a month of the year. It was an official ending to Nowruz and a beginning to the remaining twelve months of the year.

In ancient times, there was a name for each day of the month. For example, the first day of each month was called "Ormazd Rooz", and the thirteenth day of each month was called "Tir Rooz" and belonged to "Izad Tir" (the god of Tir). The word "Rooz" means "day" in Persian. The word "Tir" is called "Tishtariah" in the Avestan language. It is the same as the name of Tishter, the god of rain. So, we can say that Tir was a symbol of divine kindness among ancient Iranians because rain is symbolically equal to god's kindness and generosity in Persian culture. Nature Day is the ancient Persian tradition of celebrating the occasion of the god of rain's victory over the drought-inducing demon. Celebrating this day was customary even before the emergence of Asho Zoroastrianism (1800 BC).

As stated in the book From Nowruz to Nowruz by Mr. Kourosh Niknam (MP for Zoroastrianism), pp. 41 and 42, "the thirteenth day of Farvardin is called Tir or Teshtar." In Avesta, "Teshtar" is the god of rain. Before Asho Zoroaster, for the rain god to overcome the drought demon, people believed that they should worship this god on this particular day and ask for rain. In ancient Iran, after celebrating the 13th day of Nowruz, which was the beginning of an agricultural semi-year, Iranians went to their fields and farms or plains and deserts and the banks of rivers to worship. They would rejoice and dance and happily asked for rain.