The swamp, with its swaying reeds, pale purple water lilies and turbid waters, is full of bones.
Here is the spot where one family, fleeing an outbreak of fighting on the Upper Nile, ferried their children in a makeshift plastic canoe, only to find that it had leaked and the babies had silently drowned. Further along the waterway, people can point to the spots where lie the bones of others who did not make it.
South Sudan, which five years ago became the world's newest nation, is on the brink of a new civil war. Violence erupted last month across much of the country, forcing tens of thousands to flee their homes as the year-old peace deal that was supposed to end the last war appeared all but dead.
President Salva Kiir last week shook the nation's shaky national unity government, dismissing his deputy and longtime rival, Riek Machar. Six ministers loyal to Machar were also sacked.
It started as a political squabble, but fighting broke out in the capital of Juba and quickly took on ethnic undertones. Both men have support across ethnic lines, but Kiir is from the country's largest ethnic group, the Dinka, while Machar belongs to the second largest community, the Nuer.
The stakes in any new fighting are substantial: A new war could be more intense and more difficult to halt than the last one, which killed 50,000 people and displaced 2.3 million before it ended with an internationally brokered peace agreement in 2015.
On Friday, Kiir's government agreed to the deployment of a new African Union force to help keep the peace, but such a force would likely take months to arrive.
In the meantime, rival forces appear to be preparing for a long-running war that would likely be "very intense" in the northern Upper Nile region and could easily spread to new areas, Casie Copeland, an analyst with the International Crisis Group, warned recently.
"It's time for real talk because while the diplomats are playing games, it will be the South Sudanese who are dying," Copeland said on Twitter.
No one can describe the cost of a new war better than victims of the previous fighting. In the Upper Nile, many are still traumatized from the ethnic killings and mass rapes that occurred as recently as last year. The region, an opposition stronghold populated mainly by members of the Nuer tribe, is vulnerable to new ethnic killing should war erupt.
Survivors of last year's attacks describe widespread instances of targeted ethnic killings, many of them committed by government troops loyal to Kiir. They said soldiers raped women and girls, shot civilians, burned children alive and hunted down Nuer people hiding in the swamp.
The vast Sudd wetlands were their refuge, but many died of starvation and disease as they fled.
In recent interviews on a reporting trip through South Sudan, witnesses told of castrations of boys and incidents of cannibalism. Their stories could not be independently verified but are consistent with reports from human rights groups, who have found that while all sides committed atrocities, the majority were carried out by government forces.
Nyakun Abraham, 23, described how, a year ago, she hid and watched as five government soldiers raped an old woman outside the village of Leer and drove a stick up into her body. Falling silent as she recounted that part of the story, Abraham instead picked up a thick stick and pounded it with a heavy block of wood.
"They did this. And the old woman died," said Abraham, who said soldiers went on to attack the rest of the town. "They said, 'You are stupid Nuer. We're going to kill all the Nuer and nobody will say, 'I am Nuer.'"
Witnesses said villagers hid in the swamp in and around Leer with government soldiers in pursuit. Thousands hid on tiny islands with no food except the bitter roots of water lilies. Moving at night, families waded through the swamp for weeks to find safety in Nyal village, farther south.
Abraham spent 29 days in the swamp, wading and swimming to escape, along with dozens of other people. They put their children and elderly into makeshift canoes made of plastic sheeting tied to sticks. But one sheet leaked and five children drowned.
"Their mother cried a lot. There was nowhere to bury them. We just left them there," said Abraham, with a sad shrug.
Margaret Nyamuka, 18, fled the town of Mayendit when soldiers attacked last year, going from house to house, shooting civilians. She climbed a coconut palm to hide as up to 25 soldiers raped her 26-year-old neighbor and another woman.
"Those soldiers were lining up to rape her and she was bleeding a lot. She was crying. They said, 'If you refuse, we'll kill you.' They were laughing. They forced the children aged about 10 to watch, especially the girls, and the children were crying too.
"There were eight boys castrated. I saw the bodies afterwards on the main road. They were tied together. None of them survived. Their mothers came to bury them."
Nyamuka said she saw soldiers drag 11 people into a house and set it alight, a tactic reported by numerous survivors in different areas.
"They were old people and babies. Those people were crying until the roof fell in," Nyamuka said. "After the roof fell in, there was no more sound."
Chuol Kujien, 56, fled Leer in September, passing many villagers who had been fatally shot as she ran. Soldiers were hunting people down, she said, shooting into the water as villagers fled into the swamp.
Kujien spent three months combing the islands in the swamp before she traced her seven children, who had been scattered in the attack. For five months, she and the others lived on nothing but tree leaves and water lily roots.
"Many people died, especially children," she said. "When you got something little, you would give it to the children, so adults died too, because they were not eating."
Michael Matchok, 48, was in a cattle camp outside Leer with one of his three wives, Nyagany, 20, when soldiers unleashed an artillery barrage one morning in October. His wife and many others were killed. Matchok hid in a well with two of his sons.
"When I was in the well I saw something terrible. They killed a man and then cooked the body and they forced people to eat it," he said. "All the people who were captured had to eat that person. The women were crying and the soldiers were using big sticks to beat them."
People hid for days at a time in the swamp, with just their mouths or noses above the surface. "Many of the babies drowned. In the water, it's difficult to hide a baby," said Matchok. He escaped with his two sons, but has no idea whether his other two wives and 14 children are safe.
As soon as he got to safety in Nyal, he built a wooden canoe and returned to Leer, a four-day journey. He proceeded to rescue as many women and children as he could, making the trip seven times over two months.
In the town of Mirmir, John Koang, 39, saw six soldiers rape a young woman, about 25, who had a baby. "When they finished raping her, they tied a rope around her neck and hanged her from a tree. She was crying a lot. The more the woman suffered, the more they laughed."
With the renewed fighting, similar scenes already are beginning to replay.
Recent clashes in Juba have produced a wave of reports of sexual violence committed by soldiers. Ten humanitarian agencies warned last week that new conflict was preventing them from reaching many of the estimated 4.8 million people in South Sudan who are said to be in need of emergency assistance.
"If security conditions deteriorate further, providing aid will become logistically impossible," Zlatko Gegic, South Sudan director for the charity group Oxfam, warned in a statement. "If aid agencies cannot operate fully, the consequences could be catastrophic."