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.