Loy krathong is a major Thai Buddhist celebration where people all over the country release small floating vessels (krathong) and flying lanterns on the river and in the night. Loi Krathong takes place on the evening of the full moon of the 12th month in the traditional Thai lunar calendar and originated in the 14th century in the kingdom of Sukhothai.
Most famous celebrations happen in Bangkok and Chiang Mai as well as all across the country where there is water in a more traditional and reduced scale.
Each is supposed to prepare its own Khratong (cf. khratong workshop at the hotel) and release it later with a small candle