Cambodia celebrated the Water Festival on Wednesday, reviving the more than 800-year-old tradition in the Southeast Asian nation.

Hundreds of thousands of spectators, mostly from rural areas, flocked to the riverfront in Phnom Penh, capital of Cambodia, to enjoy an annual boat race, which is the centrepiece of the country's water festival.

Cambodian King Norodom Sihamoni, accompanied by Prime Minister Samdech Techo Hun Sen and other dignitaries, watched the race from a stage erected on the riverbank in front of the royal palace.

A total of 295 dragon boats with 19,017 oarsmen have taken part in the three-day regatta, which is held along a 1.7-km stretch of the Tonle Sap river that runs in front of the royal palace, said Bou Chumserey, vice-chairman of the boat-racing technical control committee.

"Boat race is to remember the strength of the powerful Khmer marine forces during the ancient Khmer Empire in the late 11th century," he told Xinhua.

During the reign of Angkorian King Jayavarman VII, the king had used naval forces, with boats as transport means, to fight against the invading Chams and defeated them in 1181, he said.

Chumserey said the festival is also to mark the end of annual rainy season and the unique reversal flow of the Tonle Sap river that connects the Tonle Sap lake with the Mekong river.

"It is to express our gratitude to the Mekong river for providing us with fertile land and abundant fish," he said.

A team leader of a racing boat from Southern Takeo province Sos Soeun, 46, said his boat has 73 rowers and their participation was to help preserve the age-old tradition for next generations.

"We participate in this national festival every year. It is to show our gratitude to King Jayavarman VII, who used marine forces to defeat the Cham rivals, and the water festival has been celebrated since then," he told Xinhua.

The Water Festival, which will last until Friday, is the kingdom's largest annual festival. Phnom Penh governor Khuong Sreng expected that the festival would attract up to 3 million spectators.

Besides viewing the regatta at daytime, festival-goers can enjoy the procession of illuminated floats and fireworks as well as concerts at nighttime.

"This is our Khmer tradition, and our Khmer kings have celebrated this boat-race festival since the ancient times," spectator Ho Khema, 20, told Xinhua.

"In the old days, boats had been used by marine forces to fight war against the invading enemies," she said.

Khema said she had never lost her excitement in watching the boat race although she had seen it almost every year.

"There are a lot of people and boats taking part in the festival. It's really happy," she said.

Farmer Muong Mok, 56, from Southeastern Kampong Cham province, said it would be a regret if he had not seen the water festival once in his life.

"This is the first time I come to see the water festival, it's really marvelous," he said. "The festival is to honor the heroism of our ancient kings who used boats to defend the territory."

With its long history in the country, the water festival is a special occasion for rural people to come to the capital city of Cambodia and bring home with good memories.