The Rio Blanco is about as spectacular as nature gets.
Its glacial waters tumble and churn their way down the Andes Mountains on the northern edge of Patagonia in southern Chile. It's a perfect place for nature-loving tourists, except that the river is too narrow for a raft and too treacherous for a canoe.
But that's not enough to deter the adventure seekers who have signed up for the latest thrill in extreme sports. It is called "canyoneering," or canyoning although clearly some would call it crazy.
Four tourists, and the reporter, are outfitted in wet suits. The adventure begins on dry land with a 45-minute uphill trek. As we clamber through the lush forest, there is just one nagging question:
What is canyoning?
"No idea," said 22-year-old Jessie Traub, of Milwaukee, Wis., with a smile and shrug. She's backpacking through South America with her friend Margaret Kosmack, 23, from Toronto.
"I don't know," said Kosmack when asked whether she knows what canyoning is, "but we're pretty worried about all the scrapes on our wet suits that are already there. The gear is pretty beat up." Then she and Traub laugh.
Jessica Hungelmann, 29, is visiting her dad, Jim, an athletic 58-year-old. They're from Idaho. He's in the potato business in Chile.
"I don't know what I'm doing, but I'm ready," said Jim Hungelmann. He too is smiling.
Guide Philippe Manghera of Pachamagua has made this trip about 200 times. He's been canyoning here for seven years, but it's only recently that this extreme sport has become extremely popular.
"You have to be careful," Manghera said as we arrived at our starting point: a clear, blue glacial pool fed by the first of many breathtaking waterfalls we will see.
Manghera shows us an assortment of steps for navigating the slippery water including the monkey (crawling on all fours) and the lizard (crawling on our bellies).
The entire group is outfitted with polypropylene hoods, gloves and socks. And a helmet.
We all jump in the crystal waters and our wet suits fill with cold water.
"I love it," said Traub. But seconds later, she changed her mind. "I haaaaate it!"
We intently watch a live demonstration from one of the guides who clambers up a rock cliff and bounds eagerly into the air then plunges into the icy pool.
I think I'm beginning to understand: Canyoning is a test of the law of gravity and the law of bravery.
With a mix of eagerness and apprehension the tourists follow, throwing themselves off the 15-foot cliff.
"I was like 'oh, dear God,'" said Traub after she surfaced. "You just have to do it, 'cause if you stop to think about it, you're gonna chicken out."
"I was trying not to think about it too much," Kosmack said. "I didn't get scared until the last five seconds -- right before I jumped."
The next part of canyoning we learn is called "tobogganing." Just like the sport in the Winter Olympics. Which is strange, because there is no toboggan here.
"We sit you in the white water," said Manghera as he showed us how we would slide, or, toboggan, down the smooth rocks of a chute of rapids on our backsides. "Go feet first," he said, "and when you're going, be careful with your elbows."
Like a family of obedient otters, we slide down the rapids, one after another.
The one thing running faster than the water is our adrenaline.
"Oh, this is great stuff," Jim Hungelmann said as he smiled ear to ear. "I love being in water ? hiking on these rocks. It's just wonderful."
Despite being the oldest, he is also the boldest, going up to jump three, four, even five times off the same cliffs. Some of them are 25 feet high or more.
"Maybe it's because I don't have that much time left, you know?" he said with a laugh.
Before the next toboggan run, the guides scout the river floor for sharp rocks, telling us to keep our elbows in, our feet up and our eyes open.
"It's a rush -- awesome!" Traub said as she disappeared into a torrent of white water and then plopped over an eight-foot waterfall into a deep pool below.
"Awesome!" said Kosmack, perhaps a little shocked that she'd made it this far.
As we jump, bump and slide down the river we're beginning to get a more complete picture of canyoning. You've heard the expression "up the creek without a paddle"? Well, canyoning is going to down the creek, as the paddle.
It's a safe bet that there is nothing at the theme parks back home quite like this.
Hungelmann follows the guides over one of the waterfalls headfirst.
"I just went backwards off that ledge there," he said, panting and pointing to the 10-foot drop he's just navigated. "It was awesome. ? It was just a free fall and then landing."
For the veteran canyoners among us -- the guides -- what we're doing is child's play. They fill us with awe and terror as they bound off cliffs 30 and 40 feet high, landing in pools of water that look only a little bigger than a teacup.
It looks daring and dangerous: If they don't jump way out, they'll crash into the cliff on their way down.
Alfonso Spoliansky, one of the guides, starts to say that canyoning isn't dangerous, but Manghera interrupts.
"Yes, of course, it's dangerous," he said, explaining the importance of checking the rapids and ponds for hazards after each rainfall. "It's not so dangerous when you follow the rules."
He confesses his company, Pachamagua, has had two accidents. One involved a tourist who hit his head even though he was wearing a helmet. The injury wasn't serious. The other involved a tourist who broke his leg when it got caught between two rocks.
But this extreme sport has seen much worse. In 1999, 21 young people were killed in a canyoning accident in Switzerland when flash floods inundated a narrow gorge after a rainfall. Two years later six managers were convicted of negligent manslaughter.
There is more risk here than in most sports and only fools fail to recognize that, but if fear runs through your veins, this is not the sport for you.
"You have to trust your guides," said Hungelmann. "These guides are good."
There is choice of jumps before the grand finale. Manghera offers a choice of a 25-foot jump, a smaller jump or a toboggan ride over a 15-foot waterfall.
"This is terrifying," said Traub as she stared at the toboggan ride. "I think this is a bit high for me. I'm not gonna lie, I'm a little nervous about this one."
She toboggans over the falls, no doubt concluding that the sheer force of the water won't give her time for second thoughts.
An airborne ride toward the end of the adventure introduces the uninitiated to "abseiling," a fancy word for "repelling," which is a fancy word for dropping like a stone while attached to a rope.
We all awkwardly strap climbing harnesses over our wet suits. Traub goes first. Secured to a rope, she goes headfirst over the cliff side. It is 100 feet down and just yards from the most ferocious and most spectacular waterfall of the day.
What a sensation. It is like peeking into a secret world as the water sprays in your face and lush vegetation stares you in the eye.
Then, there is one final, very high jump. Kosmack screams as she does it.
Incredibly, maybe miraculously, we all survived. We're all smiling.
And we all know what canyoning is about.