In Iran, Sizdah Bedar is a traditional Persian festival observed by many people. It occurs on the thirteenth day of the Persian month of Norouz, which is the first month of the Persian year.
Sizdah Bedar is considered the final day of Persian new year celebration. On this day, people spend the day out of doors. Many will go out for a family picnic on Sizdah Bedar, hoping that a happy time together as a family will cleanse their minds of “all evil thoughts”. And it’s also on this day that people traditionally pray for rain, though not necessarily asking for it to fall on their picnics!
There are traditional games played on Sizdah Bedar, special good luck “strategies”, and a host of other traditions that often hail back to “pagan times”. But most today who keep the celebration are Muslims and don’t necessarily believe all of the bases for the traditions kept up during Sizdeh Bedar.