Yi peng sky lantern festival San Sai Thailand. Each year, the Lanna people of northern Thailand celebrate Yi Peng, a festival in which thousands of rice-paper lanterns, called khom loi, float like balloons in the night sky. Usually made from rice paper, as each khom loi is lit, the hot air causes the lantern to rise up into the air. It is said that khom loi are symbolic of worries and troubles flying away. This is something which, seeing, would make my life complete.