The "Phi Ta Khon festival", or Ghost Festival, is held in Dan Sai, Northern Thailand every year. Around 400 years old, the festival marks a story in the previous life of Buddha, when as an Indian prince he was missing, feared dead. When he returned safe and well the celebrations were said to wake the dead, and the spirits joined in the party. Throw in a bit of animism, some fertility rites to mark the start of the rice growing season and you have "Phi Ta Khon". Friday sees traditional music and dancing, while the "spirits" roam around town scaring little kids and making girls giggle with their phallic appendages and accessories. The main parade is on Saturday, followed by a rocket launching ceremony and then Buddhist sermons.
For more see: http://latitudesandattitudes.net/2015/07/05/phi-ta-khon-the-ghost-festival-of-dan-sai/