If you're looking for something a little more thrilling than tubing down a lazy river, we've got you covered. We're not talking about in-and-out rapids, though. You better have your game on point when tackling these seven unique rivers.
You might find yourself facing 209,000 cubic feet per second of whitewater, freezing temperatures, high altitudes, steep drops, tasty waves and even floating piles of garbage. Book your tickets for the big, mean, cold and scary rivers below — but don't say we didn't warn you.
The Deepest: The Congo
Depth: Over 750 feet
Length: 2,920 miles
Why it's scary: At over 750 feet deep at its deepest point, the Congo is one scary river. Especially when you consider that it has whirlpools that are big enough to swallow a boat, like the one Steve Fisher is experiencing above. Add in plenty of treacherous whitewater and death-drop waterfalls, and the Congo could definitely make you soil your shorts.
"It was easily the closest I've ever come to dying.” Watch Steve Fisher's close call on the Congo here.
The Highest: Yarlung Tsangpo
Altitude: Around 14,760 feet
Risks: Seasickness? Try altitude sickness
Why it's scary: Starting at the Angsi Glacier in western Tibet before dropping into India, the Yarlung Tsangpo is the highest major river in the world, with its source at an altitude that coordinates to over halfway up Everest. You might guess that with that altitude it would also be the coldest river in the world, but that's not the case. See below ...
The Coldest: Upper Neretva
Temperature: Just above freezing
Length: 56 miles
Why it's scary: The Neretva River starts in Bosnia and Herzegovina and flows through Croatia to the Adriatic. Sounds like balmy beach weather, right? Think again. The river is fed by three different alpine glaciers, meaning the water is kept constantly cool — well, cold. Get a wetsuit — unless you're this guy.
The Steepest: Rio Santo Domingo
Steepness: If it were a ski slope, it'd be double black diamond
First run: Not until 2013
Other risks: Drug traffickers
Why it's scary: When kayaker Rafa Ortiz and his crew descended the Rio Santo Domingo, they claimed the steepest continuous navigable descent in the world. How steep does it get? 2,000 feet per mile, approximately — and make no mistake, that's steep. Not to mention the 65-foot waterfalls.
The Longest Underground: Sac Actun River
Fun fact: Possible location of Mayan treasures — and dinosaur bones
Discovered in: 1987
Why it's scary: We've gone high in Tibet and deep in The Congo, now let's go underground. The Sac Actun river system in the Yucatan Peninsula — which is famous for its beautiful cenotes — wanders for over 95 miles through massive underground caves. If you want to check it out, you're going to need a scuba tank.
The Dirtiest: Citarum River
Pollution level: Off the charts
Can you swim in it? See above
Why it's scary: While China's Yellow River is infamously filthy, the Citarum, which flows through Indonesia, takes the cake. Why? To start with, the 5 million people living in the river basin area, and the 2,000 different industries supported by factories there. How thick is the garbage? At places, enough to walk across. However, now that it's recognized as the world's dirtiest river there have been efforts to clean it up.
The Most Powerful River Waves: The Amazon
Wave size: Easily overhead at times
Discharge volume: 209,000 cubic feet per second
Things to watch out for: Piranhas and caimans — both bite
Why it's scary: Waves? In a river? Yep. When the tidal bore pushes water back against the Amazon's natural flow (which is the biggest in the world, by the way), the opposing forces push the water ... well, up. That creates a massive river wave. In fact, it's big enough that legendary waterman Robby Naish can surf it.
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