I recently went on a trip to Costa Rica where I did some hiking, but also was able to do whitewater rafting which was a great experience. The rapids in Costa Rica are much faster by class than I have experienced in America, even with the water being at a normal height. The gradient of the river was pretty steep as well when being compared to other rivers in the same class. The river passed through two beautiful canyons with steep walls on either side. At some points, the raft approached the walls and narrowly missed them. There were more hydraulics than I had experienced on rivers in the United States, and they had to be avoided due to their strength. If you ever are in Costa Rica, I would highly recommend going rafting.