Some 1,250 Buddhist monks took part in a beautiful candlelit ceremony at the Wat Phra Dhammakaya temple in Pathum Thani province, north of Bangkok, to mark Makha Bucha Day.
The important festival honours Buddha and his teachings, and falls on the full moon day of the third lunar month. It commemorates a day when 1,250 monks gathered to be ordained by the Buddha.
The Dhammakaya temple members include some of Thailand's most powerful politicians and is regarded as the country's richest Buddhist temple.
Makha Bucha ceremonies were also held at other Buddhist temples in Thailand, Myanmar, Laos and Cambodia.