National Geographic called the Osa the most biologically intense place on Earth, and Corcovado National Park backs the boast: scarlet macaws in pairs overhead, tapirs snoozing behind the beach, all four Costa Rican monkey species arguing in the canopy. Access is by boat or on foot with a licensed guide — book one well ahead, since park permits are capped daily. December to April keeps the trails passable.
Featured in Ten wild tropical trips for animal lovers · Tropical