There is a place deep in the canyonlands of western Colorado, high on a rugged plateau that stretches to the Utah border, that only the locals know about.
In this place, frigid mountain streams have carved out a playground of waterfalls and pools to swim in. It's called the Potholes, for the many deep pools created over millennia by the pounding current.
Only the bravest -- or most foolish -- dare to jump from the high cliffs into the water. Jumpers must clear jutting ledges to hit the deep pockets of water.
There have been accidents here. And there will be more.
"Three hundred days out of the year it could be the safest place in the entire world," said Aaron Ingels, now 23, who made a fateful trip with friends to the Potholes just over a year ago. "But on that very day ... it's not a safe place."
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Ingels and his friends still have a picture, and home video, from that day -- May 31, 2008. In one image, the friends stand around a sign that warns swimmers about dangerous waters.
What did the sign mean to them that day?
"Nothing," Ingels said.
"20/20" recently accompanied five young people from the Denver area on a return trip to the Potholes, where they marked the moment their lives changed forever ... when six good friends became five.
"It's just hard being back here and telling the story again," Kristen Kroonenberg said.
The fateful trip came during the height of the spring runoff. Snowmelt from the mountains poured down the canyons, ice cold and deadly fast.
The friends recorded a home video of roaring, rushing water.
"That hole down there was a complete boiling pot of water," said Ingels, pointing into the maelstrom. "Not a single bit of calm water in it. I had the fear of death of me when I saw that hole."
But the fear isn't readily apparent on video the youths shot that day. "First day at the Potholes," one of them, Stevie Burns, 19, said. "You know, ain't no thang."
"It was really, really loud," Kroonenberg, now 20, remembered. "It was rushing pretty hard. I just had a bad feeling about it."
But who listens to a bad feeling when the sun's warm and your friends are calling.
Burns was the first to jump.
"He came up next to us," Kroonenberg said. "We thought he was just looking down like we were. And then all of a sudden he just jumps in."
'I Knew She Wasn't Going to Make It'
"Stevie [Burns] jumped in that hole and got out so effortlessly that I just thought everything was fine," Ingels said.
For the time being, everything was fine. Then Burns decided to jump again, this time from the highest ledge.
Now the camera shows fear creeping in.
"He walked up to the 65-foot ledge and he was trying to get himself to jump off," Kroonenberg said.
For eight minutes, Burns stood 65 feet above the raging water, before finally backing down.
But on a ledge just below him, Kroonenberg had worked up the courage to jump. She recalled "falling down there and going into the water."
"I went pretty far down," she said.
And that, Ingels said, is when the nightmare began.
"The moment she resurfaced, I knew she wasn't going to make it out," he said. "Just the terrified look on her face."
Kroonenberg said, "I didn't think anybody could see me. I didn't think anybody was watching because I couldn't hear anybody. I had a hard time. I couldn't move."
Ingels was standing on a ledge yards away from where Kroonenberg was struggling, but he couldn't reach her. The fast current had formed a whirlpool, pulling her back under the falls.
"Water was going over my head," Kroonenberg said. "I was swallowing water and I just started thinking, I don't know how much water I can swallow. And I was kind of hopeless at that point."
From the cliffs above, Burns saw Kroonenberg in trouble. Minutes before, he had backed away from the highest ledge. Now, without hesitation, he jumped back into the whirlpool.
"I really, really remember because, it's the last thing he ever said," Kroonenberg said. "He said, 'Grab onto my arm tight and don't let go. I'm gonna get you outta here.'
"And I felt so safe."
"He was able to fight her back through the current to me," Ingels said. "I grabbed her and pulled her out to the side of me. And then at that point I turned to go and reach for him and he had been sucked back into the back of the hole."
In water so cold, every second steals your strength. Burns' friends held out a stick for him to grab, but it was just beyond his reach.
River Hero: He Didn't Want Us to See
"And he pushed off the wall twice, and he just didn't have enough strength," Ingels said. "His body had gotten too cold at that point.
"He started facing that wall and he didn't look at us. I think he realized that he wasn't making it out of there and he didn't want us to have to see it."
The current eventually washed Burns' body over a waterfall, and into the arms of his friends.
"We had him in the sun," Ingels said. "And I started doing CPR on him the best I knew how."
Megan Voorhorst said, "I laid on top of him to try to give him some body heat, and Kristen [Kroonenberg] was rubbing his feet. All of us were screaming at him, telling him, 'Talk to us.'"
"Aaron [Ingels] asked me to look for a pulse," Kroonenberg said. "I couldn't feel one."
"And I am screaming at Aaron, I was screaming at everybody," Bailey Roberts said. "I couldn't, from my position, do anything ... that's why I had to go get help."
Roberts ran up out of the canyon to the nearest farmhouse to call for help. Tape of the 911 call captures the desperation of the moment.
"911, what's your emergency?"
"My friend is drowning. He's drowning," Roberts said.
"Where's he at?"
"At the Potholes."
"Is he conscious?"
"Is he breathing?"
"[crying] Barely. And he's purple."
Back at the Potholes, Burns was hardly moving.
Kroonenberg remembered the moment she realized Burns was gone.
"He looked really peaceful," she said. "And that's when I thought he's not gonna make it. They had done CPR for so long."
By then, rescue teams had arrived, but there was little they could do except console Burns' friends, and carry his body out of the canyon.
"What us five experienced that day with him, nobody else experienced that," Ingels said. "Nobody else can imagine that. And we'll forever have to stick together just because of that."
In the year since Burns died, the bonds between the five friends have grown stronger, forged in grief, guilt and the love of a dear friend.
Where Stevie Burns Became a Hero
"He was so generous and would do anything for anybody, and was just the best friend anybody could ever ask for," Roberts said, crying.
"He was one of those guys that always gave me butterflies, and that's why I was so drawn to him," she said. "Stevie showed me what kind of guy I need in my life."
Ingels spoke of manhood.
"Stevie was more of a man that day than I'll ever, ever be in my entire life," he said.
For Kroonenberg, the memories are especially sharp. Her life was saved, but her savior was lost.
She said she had learned a lesson that day.
"If you have a bad feeling, don't do it," Kroonenberg said. "You're not as invincible as you think you are."
So what do the Potholes mean for the friends now?
"It feels like a part of me," Kroonenberg said. "A huge, huge part of my life. And it's the place where Stevie became a hero."
At the Potholes, the rushing water can wash away everything but their memories. The five friends plan to continue returning here, to listen to the river, and each other.
It is the place where, just for a moment, the five can be six again.