The rainforest tour is a river cruise deep into the rainforest near Puerto Limon. After riding in a motor coach to the dock we boarded open-air boats with about 30 other people. The guide pointed out several different animals along the banks of the river as we cruised along, including sloths. After the cruise (which lasts about an hour or so), we went to a mini Costa Rican village, where you could eat, listen to authentic music, drink, and even shop a little bit. On the whole it was a very low key tour, not too much physical activity required, but still enjoyable. It was a nice change from the typical motor coach tour of the city. Definitely worth looking into. If you are really into seeing the rainforest though, there is a much more in-depth tour to the rainforests that are much more inland. On this tour I think you take the aerial tram through the rainforest so you can get a better perspective of it from the canopy level. The reason why we didn't want to go on the canopy tour is that transfers are about 2 hours each way; 4 hours of travel time is a lot to invest when you are only in port for a day.