Songkran (สงกรานต์) is the most important feast for Thai people. Songkran event normally falls on the 15th full moon but the government of Phibulsongkran fixed Songkran as the 13th of April prior to World War II. Often called "water festival", Songkran is the ancient Thai New Year's Day happening mid April. Now the official Thai New Year's Day happens the 1st January.
For Songkran festival, Thai people clean everything, i.e the house, the previous year bad actions, the Buddha statues, one's own spirit. But nowadays Songkran festival is better known for its splashing water madness. Traditionally the ceremony was to pour water into the palms hands in order that bad actions, bad thoughts flow away with the water. It was a way to purify.
Children show their respect to elders by performing this water ceremony. Scented water is also poured over the shoulder and slowly down the back of the person. While pouring the water in this manner, people say good wishes and words of blessing for the coming New Year.
Sonkran is a time for celebration. Young people working in Bangkok and big cities come back to the village. They return because this is an opportunity of social reunification. They meet with their family, friends and relatives within the community.
People also donate flags (ธงปักทราย - "THONG PAK SAY") to sand pagoda. It is believed to bring luck and considered as a revered offering to the temple.
In the past, young people poured scented water over the hands of their parents and elders to show respect. Nowadays the celebrations typically degenerate. Youths wander the streets of cities in pickup trucks throwing buckets of ice water at pedestrians and motorcyclists. Others stand on street corners shooting passers-by with high-pressure water guns.
Songkran festival lasts officially three days. But it often starts one day before if the weather is very hot. All administrations and banks are closed. Most people living in Bangkok go back up-country to visit their relatives and to participate to Songkran feast. During Songkran festival there are no traffic jams in Bangkok. Many houses nationwide are put under police watch during Songkran.