As the full moon of the twelfth lunar month (usually in mid-November) lights up the night sky, throughout the Thai kingdom, hundreds of thousands of ornately-decorated krathong or traditional banana leaf floats are set adrift in rivers and waterways in a spell-binding ritual called "Loi Krathong" - the 'festival of lights". This is one of the Kingdom's oldest and best-preserved traditions.

Krathong floats in the shape of lotus blossoms are most popular and are made from materials easily found in each locality. Loi Krathong customs and traditions reflect local beliefs and cultural evolution and interesting regional variations can be seen. In Tak province, the banana-leaf floats are replaced by coconut shells which are threaded together and launched simultaneously so they appear as long chains of hundreds of glittering lights on the Ping River, hence the origin of its name, "Loi Krathong Sai".

There are various accounts about the origins of Loi Krathong. However given the river-based culture that forms the foundation of the traditional Thai way of life, it is widely believed that these are offerings made to Mae Khongkha - Mother of Waters in an act of appeasement. Many also believe that by setting adrift the krathong, one symbollically casts away one's grief, misery and ill-fortunes. Coins are also placed in the krathong as offerings. For the romantic at heart and young couples, Loi Krathong is the time to make wishes for happiness together and success in love.

At dusk, as the full moon begins to rise, the krathong is decorated with fresh flowers and the candles and incense sticks are placed in the krathong. The float is then taken to a waterway where the candle and incense sticks are lit and the krathong set adrift. The floats are carried downstream by the gentle current, candlelight flickering in the wind.

The evening's festivities consist of impressive firework displays, folk entertainment, stage dramas, song and dance. Scenes as described in ancient Thai literary accounts and still very much in existence today.

"Loi Krathong Sai" Contests To win the "Loi Krathong Sai" Contest, participating teams need to meet the qualifying criteria and do well in all three categories. 60 per cent of the total scores being allocated to the "Krathong" Contest; 20% to the processions and 20 per cent to the cheerleading teams.

The "Leading Krathong" needs to be at least 1.50 metres wide but not more than 3 metres in diameter with items placed in the float include the "pha sabong" sash, betel nuts and cloves, food, flowers, incense sticks and other offerings. The "Krathong Raft" comprises 1,000 smaller krathong floats and must not take more than 30 minutes to set adrift.

A maximum of 30 members per team prepare the floats. All team members need to be uniformly dressed in traditional Thai costumes. Team members organize the floats, light the candles and incense sticks and set the floats adrift in the respective lanes that form the "Krathong Sai Raft". The floats must be kept within a distance of 10-metres from the starting point.