Buddist Lent in Thailand
Buddhist Lent /or Khao Phansa Day/ marks the beginning of rain retreat which continue for about 3 months /3 lunar months/. Khao Phansa Day dates from Ancient India where all holy men stayed in particular place during the rain period. They avoided traveling in order not to step over the newly crops that were just planted. Lord Buddha decided to keep this tradition. So the monks gather in a temple of their choice and stay there until the end of the Lent for 3 months. While staying in the temple monks should teach young boys the Buddhist Discipline.
The ordinary people who come to the temple at the Buddhist Lent Day give candles, food and other necessary goods to the monks and finally attend a 3 circles around the temple. During the period of Buddhist Lent traditional Thai marriages are not happening because there are no available monks for the ceremony. It is again movable public holiday which happens around the middle of July.
See also
All the holidays and celebrations in Thailand