Loy Krathong!!

Loy Krathong is a festival which occurs on the full moon of the 12th lunar month, a date which usually falls in November.
Loy means to float and a Krathong is a small, hand-made “boat” or “raft” traditionally made from the leaves or bark of a banana tree and decorated with origami-esque banana leaves, flowers, candles, and incense sticks. In modern days, Krathongs are often made of specially baked bread, so the Krathongs are biodegradable, although many use styrofoam. 
Many Thais believe that celebrating Loy Krathong by offering a krathong to the Water Goddess, Phra Mae Khongkha, will bring them good luck, particularly for couples, who will go to launch Krathongs together: a particularly auspicious event if the couple crafts their own krathong, although it is more common in modern days to simply buy krathongs from vendors near the water.

During the night of the full moon, many people will light their candles and incense and celebrate Loy Krathong by releasing their floating offering on a river or other body of water. Governmental offices, corporations, and other large groups will collaborate on larger, more elaborate rafts, which are often judged in contests. Loy Krathong celebrations also typically feature fireworks displays and beauty contests.
These beauty contests are known as Noppamas Queen Contests, named after Noppamas, a consort of the King of Sukothai in the 14th century, who is thought to be the first to float decorated krathongs. 
Consequently, the tradition of Loy Kratong is believed to have begun in Sukhothai, although it is now celebrated throughout Thailand, with the festivities in Chiang Mai and Ayutthaya the most popular.
In Chiang Mai the Loy Krathong holiday is called Yi Peng. In addition to the krathongs floated in the waters around Chiang Mai, thousands of Lanna-style sky lanterns (khom fai) are released into the sky, part of the lantern oriented Lanna belief in their symbolically auspicious flames.
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