I lived in Ubon, not to be confused with it's more foreign populated Isaan neighbor Udon Thani, for several years but never was around during the Candle Festival. Since leaving Ubon I've gone back each year for the event. Held on the full moon in July which marks the start of the 'rains retreat' or 'Buddhist lent', it is the beginning of a three month period when the monks are expected to remain within the wat they reside. The holiday itself is called Kao Paansaa. Ubon marks the occasion with a major parade. It's easily the biggest even in the provincial capital. As I've come to understand it, traditionally locals would bring candles to the monks during the time they were confined within the wat . Somehow, over time, this morphed into a festival where the candles were paraded ahead of the 'confinement'. This year the full moon was on July 15 and the parade was held on the 16th. Below are some of the pictures from 2011's event.