Ten of thousands of Thais have lined the streets of the capital, Bangkok, to celebrate the 80th birthday of King Bhumibol Adulyadej, the world's longest serving monarch.
People have travelled from all over the country to catch a glimpse of the king, who has ruled the South-East Asian nation for 61 years.
The king commands enormous respect in Thailand and in recent days newspapers and television channels have been dominated by the build-up to the festivities.
Thousands packed the streets around the Grand Palace, where the king delivered a short speech calling for national unity and progress.
King Bhumibol appeared briefly and read a shortened version of the birthday speech he gave to officials on Tuesday.
Thai people, many of them wearing yellow to symbolise their devotion, have been signing greetings books and saying prayers for the monarch.
In the evening thousands of people, including members of the military and police force, gathered to light candles and sing songs for the king.
Celebrations have been going on for several days and included a religious ceremony involving Thai Buddhists, Muslims, Hindus and Christians.
A spectacular parade on Sunday saw lavishly decorated elephants and performers depicting ancient war scenes in the streets of Bangkok.