“My cousin is over there,” my guide Ketut Blen explained, pointing to a skull and bundle of clothing beneath a tatty palm and bamboo frame. “But I don't feel anything when I look at him.”

The cemetery in Trunyan, Bali, where villagers sail their dead in canoes to rot in the open air, is an isolated place. Shielded by steep and jungled slopes, it rests on the shores of a vast highland crater lake, a short boat ride from its parent village. And, on an island where most Balinese Hindus cremate their dead, Trunyan is unique.

Blen's Bali Aga people, who live in typically remote and isolated villages mainly in northeast Bali, are some of the island's oldest inhabitants: Trunyan dates back to at least 911 CE. Like most Balinese, the Bali Aga follow Bali's eccentric brand of Hinduism, but every village cluster, like the group of villages Trunyan heads, also has its own religious rituals and beliefs.

In Tenganan, the most famous Bali Aga village, that means spinning marriageable young women in bamboo Ferris wheels and weaving magic cloth. In Trunyan, that means ritual whipping with rattan shoots and exposing the dead to rot in the open air.

There are actually two cemeteries in Trunyan, Blen explained, with this one reserved for those whose life's journey counts as complete.

“Everyone here had been married when they died,” he said. “People who die before they are married, or drown in the lake, we put in the earth.”

Religion in Trunyan is even more dense with animism than most Balinese Hinduism. The village, dominated by a grand temple whose 11 pagodas mirror the 11 corpses exposed in the cemetery, has a perilous location. It perches below an active volcano on the shores of a choppy crater lake, imperilled by the twin natural dangers of fire and water.

The volcano, Mount Batur, has shaped both death and life here for centuries.

“Here we have the volcano,” Blen explained. “So it's not possible to burn people. It could cause a problem with the volcano.”

Originally for fear of enraging the volcano – now identified as the Hindu god Brahma – the dead are left to rot. The number 11 has rich significance in Hinduism, so there are just 11 arched palm and bamboo cages in the cemetery; once all are filled, villagers move the oldest remains to an open-air ossuary.

That's if there are remains left to move. Often, the bones just disappear – victims, I assumed, of the monkeys that whoop in the forest and feast on food offerings left for gods and corpses.

And yet, for all the litter and grime that fills the cemetery – a human thighbone casually discarded beside an ancient flip-flop amid a clutter of empty dishes – the place had a strange serenity. Bizarrely, there was no smell of death. The corpses, shielded by bright umbrellas and dressed in their favourite clothes, felt at peace. And the gaze of the skulls in the ossuary seemed calm, their journey over and spirits flown.

The most recent addition to the graveyard was the village priest, or mangku, who died 26 days before my visit; Blen's cousin had been there months. Because bodies may only be brought to the cemetery and its adjoining temple on auspicious days, and the family has to raise money for the funeral, some corpses stay at home for days or weeks beforehand. Villagers use formaldehyde to stop their loved ones rotting over the long wait.

The hillside village of Puser, part of Trunyan's cluster, also has an open-air cemetery. As our boat passed, the rubbish-dump reek of rotting bodies was evident 100m out on the water.

But as we arrived in Trunyan cemetery, there was no smell at all. I looked through a palm leaf cage into the empty eyes of a man whose blackened flesh still clung to his skull, and caught only the faintest whiff of decay.

There is more than formaldehyde to the missing stench, it seems. A towering, tangled, mossy tree that looks like an ancient banyan dominates the open-air cemetery. Locals believe that the tree, called Taru Menyan, or “fragrant tree”, overpowers the rotting smell.

“This tree is magic,” explained Blen's friend, Ketut Darmayasa. “At home the bodies would smell. Here, it's only because of the tree.”

It's not just the death ritual and the magic tree that makes this lakeside fishing village unusual. The entire village still gathers to make communal decisions at the bale agung, a cluster of open-air platforms that form the heart of the three-tiered village. And once a year, around October, the young men dress up in elaborate costumes of fringed banana leaf and brandish rattan shoot whips in a ritual dance called Brutuk. Its aim? To sanctify the temple, thus keeping the village and villagers safe.

But it's the cemetery, with its strange serenity, that defines Trunyan. And there, surrounded by reminders of the mortality we all share and the death that will come to all of us, I asked Blen how he could look at the decaying remains of the cousin he had loved and not feel grief.

He and Darmayasa discussed a while in Balinese. “He is only sad at home,” Darmayasa said. “[In the cemetery] he doesn't feel any grief.”

“Why” I asked again.

“Because it's our culture,” Darmayasa said simply.

For in Trunyan, as everywhere, both death and grief are cultural acts: it's just more obvious here.

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