Tsechu (literally "day ten") are annual religious Bhutanese festivals held in each district or dzongkhag of Bhutan on the tenth day of a month of the lunar Tibetan calendar. The month depends on the place, but usually is around the time of October. Tsechus are religious festivals of Drukpa Buddhism. The Thimphu tsechu and tha Paro tsechu are among the biggest of the tsechus in terms of participation and audience. Tsechus are large social gatherings, which perform the function of social bonding among people of remote and spread-out villages. Large markets also congregate at the fair locations, leading to brisk commerce.
The focal point of the tsechus are the sacred Cham Dances, which are banned in neighbouring Tibet. These costumed, masked dances typically are moral vignettes, or based on incidents from the life of the 9th century Nyingmapa teacher Padmasambhava and other saints.
Most tsechus also feature the unfurling of a thongdrel (or thangka) - a large tapestry typically depicting a seated Guru Rinpoche surrounded by holy beings, the mere viewing of which is said to cleanse the viewer of sin. The thongdrel is unrolled before dawn and rolled up by morning.
Information based on http://en.wikipedia.org/wiki/Tsechu