Astrological New Year
Songkran, Bun Pi Mai, Thingyan, Cambodian New Year, Buddhist New Year, Sinhalese New Year, Tamil New Year
April 13th - 15th (varies each year, can go on for days)
Thailand, Laos, Myanmar, Cambodia, Sri Lanka
Whenever they're held, New Year celebrations are typically a time for cleansing and starting afresh. This may explain the Thai Songkran (and Burmese Thingyan) tradition of throwing buckets of water over anyone within range - hose-pipes and SuperSoakers also seem popular! In Cambodia and Laos the situation is made even messier by the addition of talc, used to mark people with a blessing for the coming year - sometimes by smearing it all over their faces.
In Thailand, Songkran is big, and has proven quite a draw for travellers keen to join in the mayhem. In some towns - eg Chiang Mai - the festival goes on for days. Although Songkran can get rowdy, it has a gentle side, too; religious statues are paraded through the streets on ornate floats to get their own cleansing, and icons in wats and personal shrines are washed with fragrant water.
New Year festivities elsewhere in South-East Asia vary from messy mayhem to more sedate: Myanmar's version, Thingyan, rivals Thailand; Cambodian Buddhists wash themselves with holy water & clean their Buddha icons; in Laos, there is much mutual soaking, but statues are also washed and decorated with flowers, games are played, and captive animals are set free. Sri Lanka also celebrates New Year at this time of year, with rituals that blend Buddhist, Hindu and long-held local traditions.