We spent a few days in Baños, which is in central Ecuador, and is known for adventure sports and as a jumping off point for trips into the Amazon. We're going to wait until Bolvia for our Amazonian adventures as we've heard that the tours in Baños don't go that far into the jungle.
During our time in Baños we attempted a 60km bike ride to Puyo (bikes were $5/day). This is touted as "mostly downhill" which is true, but the uphill portions are... mountains. That, combined with the altitude and a heavy rain storm stopped us about 18km in. At 18km you can visit El Pailon del Diablo which is a waterfall towards the bottom of a canyon. We parked our bikes and headed down to take a look. It had rained the night before and the waterfall was in full force. We dawned our rain gear and out onto the viewing deck. Well worth the $1.50 per person to see.
We hiked up the trail (significantly less fun than the way down) and had a relatively expensive ($5) trout lunch. We then headed out just as it was starting to rain. We made it another kilometer or two and the rain really started to pick up. We were exhausted from what we'd already encountered for the day so we turned back. Getting back to Baños involved flagging down a truck driver, throwing our bikes into the back, and hopping into the back ourselves as the front seat was already occupied by other bikers.
On our second day we rented a "Boogie" which is essentially an all terrain go cart type thing. We drove that out the same road which was quite fun. On our way back the rear wheel started to go flat so we quickly made our way back to Baños.
Now, Baños has its name due to the hot bathes that are here from the local volcano. You'll notice that I did not, at any point, mention visiting them. We decided to skip the bathes, they look dirty and are essentially large public swimming pools that are really hot. If you decide to visit them, let us know how they were.
Baños is really touristy, but certainly worth spending a couple of days in. The activities are reasonably priced and despite our mechanical/weather related issues we had a lot of fun.