Tasnim | M.Hasan Zarifmanesh & Amin Ahouei: Iranians are preparing to celebrate Yalda Night, an ancient cultural festival marking the arrival of winter and the longest night of the year. People mark the festive occasion in Iran and Central Asian countries such as Afghanistan, Tajikistan, Uzbekistan, Turkmenistan and some Caucasian states like Azerbaijan and Armenia on December 21 every year. Yalda Night is one of the oldest Persian traditions and its history dates back to thousands of years ago. Ancient Persians believed that on this night, the sun was saved from the claws of darkness thus materializing the triumph of good over evil.