The ancient custom of a fire festival is another way to welcome the new year. Long ago, in an effort to ward off evil spirits, people lit bonfires and placed clay figurines of animals and ancestors on their rooftops. Today, children celebrate the last Tuesday night before Nowruz by singing and dancing, dressing up as ghosts, and banging spoons together as they trick-or-treat from door to door. They also jump over fire—an activity called chahar-shamba suri—to get rid of the troubles of the old year and to celebrate the victory of light over darkness.