Favorite thing: A popular sight in the rain forest is the butterfly. Arenal has no shortage. With patience and luck, you will have some great experiences. They can be anywhere from right outside your hotel door to some local trails that are on the grounds of many of the hotels in the area.
Favorite thing: On our way to Cano Negro, we stopped in a small village called Muelle, to have a look at this tree. What's so unsual about this tree, you may well ask. We asked that same question too. It's not until you look very closely that you realise, that the tree is full of huge iguanas. Those fat brown things are not branches, they are reptiles! There must have been hundreds of these things, and we were at a loss to explain why they congregated in this particular tree. A most peculiar sight!