Unless you're heading for it, it's not likely you'll accidentally run across INBio Parque, the National Biodiversity Institute of Costa Rica, a expansive ecologically themed park located on the outskirts of San Jose. It's well worth pointing your GPS in the right direction or arranging a day trip from your hotel to this fantastic introduction to and overview of Costa Rica's natural attractions. 
Photo courtesy of Sophia LaMonica
INBio is a non-profit organization that was founded in 1989. It is dedicated to scientific research and promoting the importance of conserving the country’s rich biological diversity. Essentially, it's a one-stop introduction to Costa Rica, offering tours and interactive experiences aimed at bringing families, students and visitors into closer contact with Costa Rica's natural resources. 
Photo courtesy of PENyshot
Watch a short video presentation about INBio and biodiversity in Costa Rica before embarking on a series of trails that bring to life, literally, different types of Costa Rican forest: rainforest, pre-mountainous forest, wetlands and dry forest. From a safe distance, but as up close and personal as you'd want to be, observe poison dart frogs, butterflies, iguanas, sloths, caimans, birds, turtles and snakes in their virtually natural habitats. Other stops along the way are the mushroom exhibit, an exotic flower garden with orchids, heliconias, bromeliads and a 300 million strong insect collection.