Some say it’s the thrill of a lifetime. Mastering the wild rapids of America’s great rivers can certainly be a heart-stopping adventure. There are plenty of routesin the U.S. that have options for first-timers, whitewater experts, and everyone in between.

Rivers are graded I-IV classes. Class I is mild enough for your granny, and Class V trips often require previous rafting experience for very good reason. Looking for rowdy fun? Classes III-IV are your range.

If you’re ready for some excitement and challenge, here are 6 places to earn your soaking-wet sense of accomplishment:

Nenana River, Alaska

Alaska’s Nenana River is fed by glacial melt from Mt. McKinley and flows north through the mainland to Denali National Park. As well as superb whitewater, a trip here offers wonderful wildlife sightings from grizzlies to moose to the spawning salmon. There are more than ten miles of challenging class IV rapids, and this river is bordered by deep canyons where golden eagles and wild sheep are abundant. Those impressive rapids will give you a full-body workout. Try the day trip navigating the river’s Canyon Run.

Chattooga River, Carolinas/Georgia

One of the most beautiful free-flowing rivers in the country, the Chattooga River is known as a legendary Wild and Scenic River and is the premier destination for wilderness rafting in the Southeast. In springtime there’s a raging class V section for experts, but the river also offers light class I-III sections for those who want to cool off and get some experience. It’s near enough to Ashville, N.C. that rafters can quickly be in a hub packed with awesome food and off-river entertainment after their time in the wild gorges banking this beauty.

Gauley River, West Virginia

When’s the best time to go? On six weekends in September and October when the Corp of Engineers draws down Summerville Lake and water rushes into the riverbed. Expect explosions of whitewater churn, but take time to look at the huge boulders, towering canyon walls and the hardwood trees painted in fall colors. The Gauley River has a 35-mile stretch of class V challenges through gorges primed for adventure. There are more than one hundred rapids among the most technically difficult in the country that attract the sport’s ardent adrenaline junkies.

Tuolumne River, California

California is blessed with several excellent rafting choices, but the Tuolumne River stands out as an exceptional whitewater destination. The river drains out of Yosemite National Park and plunges into Cherry Creek – thought by many to be the most intense stretch of commercially-rafted whitewater in the country. Less intense, but surrounded by equally stunning Sierra Nevada scenery, the Main Tuolumne section offers an 18-mile course that can be taken on over one or more days.

Arkansas River, Colorado

This is the ultimate rafting destination in the Rockies, flowing through a wide glacial valley surrounded by towering 14,000+ foot peaks before it plunges into the 1000-foot deep slot canyon of the Royal Gorge. You’ve got choices here from mild to wild: Granite Gorge is class II-III, the Numbers section is rated class III-V, and Royal Gorge turns up the dial along its path from class III to V. Multiple adventure companies offer single day and extended trips that start with an easy float and escalate to the perfect thrill, all set against a backdrop of rugged mountain terrain.

Salmon River, Idaho

The Salmon River can claim the most options for trip length and diverse scenery and wildlife as it cuts through the middle of the largest contiguous roadless wilderness area in the lower 48 states. It has become one of the world’s most popular whitewater destinations because of rapids up to class IV and glorious alpine and forest scenery. There are more than 300 ratable rapids and 6 natural hot springs along its path. Take in the high country forests, towering granite canyons, and the vast stretches of grasslands, and be on the lookout for wildlife, including black bear, bighorn sheep, moose, and even mountain lions. Outfitters offer everything from day trips to excursions of a week or more.

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