One of the oldest cities of Iran, with desert architecture, an important Zoroastrian center since Sassanian time  that has kept Fire Temple and Dakhmehs ( Towers of Silence) , a prosperous city standing at the cross - roads of the most important caravan routes from central Asia and India to the south and West   has the name of Yazd .  Marco polo, who came here on his way to China in 1212, called it  " The Good and Noble City of Yazd " .