As twin brothers lay dead along the bobsled track at Canada Olympic Park and other friends with serious injuries shivered in the bloody ice, Mark Lyons lifted his voice in a song of worship.

Another teen, Wilson Schultz, knelt in the dark praying at the side of a friend with serious head injuries until firefighters arrived.

Even the fact that the brothers who died were found side by side is viewed as a sign from God.

This Christian faith helped sustain the surviving six teenagers on that unthinkable night in February 2016, when a high-spirited stunt after a church-run youth group meeting went terribly wrong.

Mark Lyons, left, and David Carr displayed optimism even early on in their physical recovery. They were among the six survivors after eight teens crashed while tobogganing after-hours down the bobsled run at Canada Olympic Park in the early hours of Feb. 6, 2016. (Caleb Hettinga)

​A year later, the survivors hope to help deepen the faith of others by sharing intimate details about the tragedy that killed Evan and Jordan Caldwell and left three others with permanent head injuries.

"I kind of feel like that's the reason that I'm kept around, 'cause we could have all easily died," Danny Spalding said.

He says he and the others are speaking up for the first time in an exclusive interview with CBC News to show that "people can have the same peace as us."

Which isn't to say they don't also live with enormous regret over the decision to sneak onto the high-speed ice track after-hours at Canada Olympic Park.

'I definitely grappled with the whole idea of, well, if God's a loving God why would he allow this to happen? Why would he do this to me?' says Hettinga, who has undergone six facial surgeries and lost sight in his right eye. (CBC)

"Every time I look in the mirror, I am reminded, because obviously my face has been deformed in a sense," said Caleb Hettinga, now 19, who has undergone six facial surgeries and lost sight in his right eye.

"I definitely grappled with the whole idea of, well, if God's a loving God why would he allow this to happen? Why would he do this to me?" Hettinga said.

"But all the good that has come out of this story has really changed my perspective. And even now, only a year out, we still can't see the big picture and the whole plan that God has."

'There's no way it could go wrong'

Feb. 5, 2016, began as many other Friday nights for the eight teenagers.

Danny Spalding, David Carr and the Caldwells were attending a youth group run by the Rocky Mountain Calvary Chapel in Calgary.

Spalding's two mountain biking friends from Wetaskiwin, Alta. — brothers Wilson and Eric Schultz — were in town for the weekend and tagged along.

Twins Jordan and Evan Caldwell were remembered by their family as 'bright lights to all that knew them.' The fact that the brothers were found side by side after the tragedy despite having been on separate sleds is viewed by at least one survivor as a sign from God. (Submitted by the Caldwell family)

Hettinga and Mark Lyons were playing basketball at their high school, the Heritage Christian Academy.

"I think of this crew as kind of like 'youth group plus church friends plus a few others.' We are all Christians. That's how we all came together," said Carr, now 19.

But the plan to go "sledding" or take plastic toboggans down the bobsled track at Canada Olympic Park had been in the works ever since it was successfully tried a week earlier by three of the teens: Spalding, Hettinga and Evan Caldwell.

"It's scary…. The first time we did it we didn't know what to expect," said Spalding. "But after that, for me anyway, I just felt that it was the perfect thing. It gets your adrenalin going, but there's no way it could go wrong."

On that first night, the trio used helmets and head lamps. They did a few laps. At first it was one person per sled, but Hettinga thought they weren't going fast enough.

The teens didn't realize that staff at the Olympic park had strung a chain across the point where the bobsled and luge tracks merged in preparation for training that weekend. (Erika Stark/CBC)

"Me and Evan came to a stop a couple of times: we were going too slow," Hettinga remembered.

"It was definitely not too dangerous that time, then we decided to double up and go a lot faster down it."

The worst that could happen — they thought — was they'd fall off their sleds and slide to a stop further down the track.

So as they shared their stories, boasting, they decided to return with more friends.

The return

On Feb. 5, 2016, the group of eight met at the top of the hill.

They scaled the perimeter fence with three plastic sleds in hand and headed towards the platform of the track.

It was shortly after midnight on Feb. 6, and they recall it being fairly dark with the exception of a few streetlights.

This time there would be no head lamps and no helmets.

"The [fact that] they had gone before took out a lot of doubts in our minds about just like normal precautions you would take for something like that, like checking ahead, and everything, just kinda slipped under the radar," said Wilson Schultz.

'I thought I was going to bleed out and die'

The first sled had Hettinga in the front, Lyons in the middle and Evan Caldwell in the back. In the second sled, Spalding sat up front, Wilson Schultz squeezed in the middle and the younger Schultz was at the back. Jordan Caldwell perched at the front of the third sled, with David Carr in back.

David Carr, Mark Lyons and Caleb Hettinga, shown after meeting the firefighters who were first at the crash, all survived but with serious head injuries. (Clyde Carr)

One by one they pushed off.

What they didn't know was that staff at the Olympic park had strung a chain across the point where the bobsled and luge tracks merged in preparation for training that weekend.

"I remember flying around the corner and seeing something and then I blacked out," said Hettinga.

He woke up moments later and couldn't speak or see.

Wilson Schultz and the two others he was with on the second sled escaped relatively unscathed, a 'miracle' he attributes to a Lord's Prayer that was said as they pushed off at the top of the bobsled track. (CBC)

"I thought I was dead for sure. I thought I was going to bleed out and die," he said. "I was starting to struggle to breathe because stuff was lodged in the back of my throat."

Hettinga and Lyons from the first sled ended up lying together in a corner of the track under a tarp, with major head and facial injuries. They didn't know immediately that their sledding mate, Evan Caldwell, had been killed, falling off the track near the chain.

'It's a miracle we passed through it'

Back on the platform, the remaining teens were unaware of any problems. When Jordan Caldwell gave a push-off to the second sled, he recited the Lord's Prayer.

Wilson Schultz believes those last words saved his trio from serious harm.

Paper flowers, candles and other mementos surrounded the photos of Jordan, left, and Evan Caldwell, 17, at one of two memorials set up at Westmount Charter School in Calgary after the twins died. (Evelyne Asselin/CBC)

Schultz broke his ankle, while his brother Eric and Spalding walked away.

"It's a miracle we passed through it," he said.

"It was right in front of us and then all of a sudden we were just through it."

There are fewer details about what exactly happened on the third sled, other than it hit the chain, too. Jordan Caldwell was killed and Carr received a brain injury that impaired his memory.

"I'm lucky enough not to remember any of it, because it's still been hard: just the grief itself and the loss of a lot of things including functions of my body and also really, really good friends," said Carr, whose injury affects the right side of his body. He still faces another year of recovery.

First responders found the injured teens scattered along the track.

He was completely destroyed but he was singing a song to us, a worship song, to help us all get through it. We were all praying. - Wilson Schultz

The Caldwell brothers were found together, lying next to Carr, close to the chain.

"Them being on different sleds and with the amount of us there, the odds that they would pass away side by side, together that night, and only them, is something I think God meant for that to happen. I know that's hard for people to wrap their heads around," said Carr.

The teens say that even though some of them had just met that night, they all pulled together through prayer to get through the dark moments, waiting for help to arrive.

"It was pretty amazing," said Wilson Schultz.

"[Mark] was completely destroyed but he was singing a song to us, a worship song, to help us all get through it. We were all praying."

Hettinga recalls hearing Wilson shout out to Danny to call 911.

"Then Wilson started kneeling down and praying for me the whole time until the firefighters arrived," said Hettinga.

Now the surviving six want to share their story to inspire others to deepen their faiths.

'A lot of bad things happened, but also God showed himself in a lot of amazing ways. I don't wanna try to ignore that,' says Wilson Schultz, right. (CBC)

"It was really sad what happened, but it was really also cool to see some good things that came out of it, even just everyone who rallied together," said Lyons.

The group would like to thank everyone who responded to the scene, and provided care in the days and weeks that followed.

They also hope to prevent similar tragedies by speaking out.

"Just to think through, 'What are all the consequences to that decision you're making,'" said Hettinga.

"Our accident didn't just affect us. It affected our friends' family and the whole city. And we're super sorry for the decision that we did make."

Hundreds gathered at a packed Centre Street Church for the twins' memorial service, bringing flowers, cards and handwritten notes to lay at tables in the foyer. (Kate Adach/CBC)

The survivors say it's also been a lesson in loss. They miss Evan and Jordan, but believe their good friends are happy where they are now.

Spalding summed up their shared belief that the twins are happy in the hands of God and "probably having the best times of their lives" in heaven.

"We know that we're going to see them again," he said.

"They're gone; we're going to miss them for maybe a year, maybe 80 years — who knows? — but it's not the end, right? So that's kind of what keeps us from breaking down."