The festival lasts for three days between late March and mid-April in numerous temples in north Thailand and is dedicated to the pre-teen boys that are to go to monasteries for some time.
On the first days, the families of the boys gather for some feasting and afterwards the boys are brought to the temple to have their hair and eyebrows shaved off completely. They are also ritually purified and paraded with accompaniments of flutes and drums and cymbals. On the second day, young boys put on white turbans and are paraded through the town to the temple, where they give offerings to Buddha.
The boys are often riding horses. They pray for blessings from the spirits and take part in the celebration which features dancing and music. Finally, on the last third day early in the morning, the boys are transformed into "Jewelled Princes" with a help of make-up and white turbans decorated with flowers. The boys are carried on their personal thrones to the temple, where they will ask the Abbott for permission to be ordained. A very colourful and extravagant event that should not be missed!
Most vibrant celebrations of Poy Sang Long Festival you might witness in two temples of Chiang Mai region: Wat Ku Tao and Wat Pa Pao.