Phnom Penh, Cambodia - The crowds arrive before dawn, heading through the temple gates from 4 am. Dressed in their finest silk clothing, people come throughout the morning with food and flowers, and lay them before lines of monks who chant prayers for the dead.
The ceremony, known as Pchum Ben, is one of the most important for Cambodia's majority Buddhist population. It lasts for 15 days, and this year ends on October 9.
For the dead, Pchum Ben marks the period when their spirits are allowed to leave hell and visit the temples to seek food. For the living, it is a time to bring offerings and remember their relatives.
Cambodia's turbulent history means many have vivid memories of loss. As many as 2.2 million people died out of a pre-war population of 8 million during the Khmer Rouge's rule between 1975 and 1979.
At Wat Langka, one of Phnom Penh's most important Buddhist temples, the Venerable Hou Sarith, a senior monk, says most people lost relatives during that time.
"The people believe that if they give this food to the monks, then the monks, who have high morality, can deliver that food to those spirits," he says.
And, he adds, bringing food also results in the living acquiring merit.
Outside Wat Langka's central hall, Va Kimchheang, a civil servant, says the ceremony is a time for her family to come together.
Va Kimchheang was a child during the Khmer Rouge regime, and has only vague memories of that time. But the emotion of loss is close to the surface, and she fights back tears as she speaks.
"I lost many relations during the Pol Pot regime: My aunt, my brothers, and there were others too," she says.
Today she has brought her two young children, who join her in lighting incense for the dead. Wat Langka is the ninth pagoda they have visited.
She says the spirits will receive the food that they offer to the monks.
"We of the young generation wish that those spirits who are in a bad place can go to a better place," she says softly. "And we wish that those who are unhappy will be happy."
With that, Va Kimchheang heads into the main hall and sits on the floor with other faithful. Across from them, behind a low wooden table laden with baskets of food, are several dozen orange-robed monks waiting to chant prayers.
At one end of the room a reclining Buddha stretches behind a bank of incense sticks, while at the other a band plays music on traditional instruments under a ceiling showing images from the Buddha's life.
It is a peaceful scene that contrasts starkly with the bloodshed of the 1970s. Some people believe that the spirits of those who die violently - as so many did under the Khmer Rouge - are malevolent.
Hou Sarith says that is not necessarily the case. The spirit's state, he says, depends on the person's thoughts at the time of their death.
"If the person is angry at the injustice of being killed, then the spirit will take that anger into the spirit world," he says. "And then those angry spirits will not be able to find a place where they can be born again."
Although Pchum Ben is an ancient ceremony, it has started to catch up with the 21st century. A year ago Hou Sarith started to use the internet to share the festival far beyond the temple precincts.
His laptop is logged in to an online chat room called PalTalk, where several dozen devotees from the United States, Canada, Europe, Sri Lanka and Thailand are signed in.
The monks' prayer chants drift in through the barred window. Hou Sarith turns up the sound on his laptop, and a lone voice from, as it turns out, the US state of Colorado, rings through the tinny speakers.
He says he and the other monks around the world take it in turns to lead the daily sermons.
"Today my colleague, the Venerable Karna, is delivering the sermon. And tomorrow I am," he says. "With this I have the ability to deliver the Pchum Ben sermons to many people."