Loi Krathong festival is an ancient Thai tradition, which is takes place on the evening of the full moon of the 12th month (usually November). It is a very beautiful scene, with the full moon shining down on the river, perfect for floating Krathong. Loi (ลอย) means 'to float', and Krathong (กระทง) is the item which is floated down the river (see further).