Activities: going to the beach (I personally loved Playa Espadilla and Playa Biesanz) and of course visiting the Manuel Antonio National Park. I suggest getting a guided tour if you visit the park because the local guides know where to find the animals and have binoculars so you can watch them closely. There are monkeys, sloths, frogs, birds, etc. They also warn you almost everywhere about snakes, but I must say that I never saw any near the trails, they don't like people and noise, so that wasn't a problem at all (and I'm REALLY afraid of snakes). Also, if you have the chance to do parasailing on the beach i totally recommend it. It's quite expensive, but it's worth it.