Places that get lots of rain—like tropical countries covered in rainforest—generally have raging rivers. Go figure. But most travelers to these places are too busy lubing up with sunscreen at the beach to notice or care. The advantage to rafting in the rainforest is that it's generally a lot warmer than the Snake or Colorado. Plus, the monkeys swinging in the canopy above you make for great pictures.
The runs near the Caribbean coast of this Central American country are short, but get the heart pounding. One of the region’s most famous is a 20-mile stretch of the Cangrejal River, which drains into the sea from the heart of the Nombre de Dios mountains. The upper and middle portions are strewn with Class V rapids, but become more navigable as the river plummets through the jungle, down to Class II through IV runs in the lower section. Omega Tours runs eight-hour trips, starting in the upper section, for $135.
The lifeblood of the Dominican Republic is the twisting, 80-mile-long Yaque del Norte River, which originates in the country’s central mountains and eventually dumps into the sea in the Bahia de Monte Cristi to the northwest. Trips begin near the high-elevation town of Jarabacoa, and last for about a half-day, passing through a washboard of churning Class III rapids (and maybe class IV if the water is high). Jarabacoa Gold Company is one of a handful of operators. Trips cost $75.
Though I didn’t do the math myself, I've heard claims that there are more rivers per square mile in Costa Rica than in any other country in the world. Given the amount of rain that drops onto the slopes of its tall volcanic peaks, this statistic doesn’t seem like a stretch. The premier paddling waterway is the 100-mile-long Pacuare River, ornamented with class IV and V rapids, and home to last year’s World Rafting Championships. Day trips will take you through the rollicking lower stretch, but the best way to see the river is to take a three-day excursion that starts on the upper half and heads down through a world of virgin rainforest. Green Frog Rafting offers day trips that start at $95.