By Stephanie Gregory

River rats and thrill seekers, those who love rapids that churn the water and stomach, will love these destinations. If the foaming roller coaster of rapids stirs your soul, so too will the scenery.

1. Futaleufu River White Water Rafting, Chile.
The Mapuche Indians must have had rafters in mind when they named this the "Big River." Bisecting the northern tip of Patagonia, the 40-mile stretch of raftable Fu contains a healthy smattering of the world’s most difficult Class V rapids. A favorite is the "Throne Room," (aka "Thrown Room") a massive, roiling wave train followed by a house-size boulder, which forces rafters to choose the lesser of two evils: Run the "Toaster" to the left or paddle the enormous, raft-swallowing hole to the right. Either way, somebody’s likely to swim.

2. Cherry Creek/Upper Tuolumne White Water Rafting, California, U.S.A.
Snapshots of Cherry Creek rafters usually show the boat at a 90-degree pitch, almost as if everyone is paddling straight to hell. But survivors of this nine-mile Class V river, comprising one mile of Cherry Creek and eight miles of the Upper Tuolumne, get both a slice of heaven and hell on this run. Be prepared for holes, falls, and ledges, all surrounded by spectacular mountain scenery. The Tuolumne, designated a National Wild and Scenic River, is just north of the Yosemite border in Stanislaus National Forest.

3. Zambezi River White Water Rafting, Zimbabwe.
The put-in at the base of Victoria Falls is dubbed Boiling Pot, thanks to the frothy stew created by the water’s 350-foot freefall. It’s hard to top this grandiose send-off--after all, you’re at the base of one of the world's Seven Natural Wonders--but the Zambezi has infinite attractions. Paddle from one to seven days past 400-foot-high basalt gorges, Class V rapids that produce 20-foot-high waves, and hungry crocodiles with an eye out for fresh flesh. Before you go, send an offering to Nyaminyami, the god of the water you are about to set into. Just to be safe.

4. Great Bend of the Yangtze River White Water Rafting, China.
Hard to imagine, but the canyons surrounding the Great Bend of the Yangtze make the Grand Canyon look downright Lilliputian. The trip begins at Tiger Leaping Gorge, where the canyon is twice as deep as the Grand and the river is one-third as wide as the Colorado, conditions that add up to a water flow that’s six times more powerful. To cap off the drama, the Dragon Shan Snow Mountain rises 12,000 feet from the crashing water. First rafted by the Chinese in 1986, this Class IV-V, seven-day run is obviously not for claustrophobics or first-time rafters.

5. Río Upano White Water Rafting, Ecuador.
Running through the Amazon Basin from the spine of the Andes to the border of Peru in southeastern Ecuador, the Río Upano is hard-core-lite, with just enough Class III and IV water to make things interesting, but not so much that it makes the 80-mile journey a heart attack waiting to happen. Besides, with the river’s warm water, the tropical heat, and cascading 100-foot-high waterfalls every few miles, you’ll be doing everything in your power to partake in riverine aquatics. Added perks include encounters with native Shuar people navigating the river via homemade boats and the thrilling calls of more than 1,500 bird species.

6. Magpie River White Water Rafting, Quebec, Canada.
High thrills, small crowds, and an aircraft-assisted portage attribute to the Magpie’s legendary status among seasoned rafters. For a river just 500 miles from Manhattan, the Class V Magpie’s remoteness is unimaginable, boasting everything you’d find in Alaska short of glaciers and grizzly bears. The 40-mile runnable stretch starts with a float-plane descent into Magpie Lake, followed by five days of alternately paddling and airlifting around obstacles (particularly the 80-foot Magpie Falls).

7. Karnali River White Water Rafting, Nepal.
The Karnali’s source is Tibet’s sacred Mount Kailash, possibly the reason this Class V river is so divine. A 12-hour drive west from Kathmandu, topped by a two-hour hike to the put-in, the "Gnarly Karnali" is Nepal’s most remote rafting river. Draining most of western Nepal, the Karnali boasts emerald-green water, deserted tropical beaches, and wicked Class IV-V swells, with banks topped by Nepalese villages rarely visited by the burgeoning number of Western tourists. Handily, the river ends in Royal Bardia National Park, one of the best places in the world to spot a Bengal tiger.

8. Gauley River White Water Rafting, West Virginia, U.S.A.
Back in 1992 Congress mandated that, between Labor Day and late October, Summersville Dam must release 2,800 cubic feet of water per second for the purely hedonistic pleasure of rafters and kayakers. For those 22 days, you can catch this Class V pool-and-drop river at full throttle; you’ll feel like a cowboy atop a bucking bronco. But don’t get thrown: The Gauley river runs so swiftly that it’s famous for its undercut ledges. Indeed, along the 28-mile run there are precious few spots between the 100 or so Class III-V rapids to catch your breath enough to enjoy the steep Appalachian scenery.

9. Middle Fork of the Salmon White Water Rafting, Idaho, U.S.A.
Cutting a 100-mile swath through America’s most remote country, the Frank Church/River of No Return Wilderness, the Middle Fork of the Salmon is the George Washington of American river trips. But the Middle Fork’s appeal is less its 100 frothy Class III-IV rapids--which, incidentally, are oftentimes followed by lazy stretches of gentle currents--and more its idyllic surroundings: Hot springs, petroglyphs, and cascading waterfalls, as well as big horn sheep and elk grazing the grasslands amid crumbling 19th-century homesteads, keep folks stimulated when they’re not in full paddle mode.

10. Victoria Nile White Water Rafting, Uganda.
This is relatively new territory for paddlers, with a first descent in 1996 by a Minnesotan of questionable sanity. As such the 300-mile Victoria Nile, which flows from Lake Victoria to Lake Albert, still holds ample surprises--the scariest being a 55-mile stretch that drops one continuous Class IV-V rapid after the next for 800 feet. A quarter of that drop, by the way, takes place at 200-foot Murchison Falls, a mandatory portage.

Stephanie Gregory is a regular contributor to iExplore.