3 Best Sights in Costa Rica

At the confluence of the Puerto Viejo and Sarapiquí rivers, La Selva packs about 700 bird species, 700 tree species, and 500 butterfly species into just 15 square km (6 square miles). Sightings might include the spider monkey, poison dart frog, agouti, collared peccary, and dozens of other rare creatures. Extensive, well-marked trails and swing bridges, many of which are wheelchair accessible, connect habitats as varied as tropical wet forest, swamps, creeks, rivers, secondary regenerating forest, and pasture. The site is a project of the Organization for Tropical Studies (OTS), a research consortium of 63 U.S., Australian, South African, and Latin American universities, and is the oldest of three biological stations OTS operates in Costa Rica. (OTS also operates one research station in South Africa.) As a biological station, researchers and their assistants are often in residence, and if you encounter them over breakfast or in the field, there can be an opportunity to learn more about their projects. To see the place, take an informative three-hour morning or afternoon nature walk with one of La Selva's bilingual guides, who are among the country's best. Walks start every day at 8 am and 1:30 pm. For a completely different view of the forest, set off on a guided two-hour walk at 5:45 am or the night tour at 7 pm. Walk-ins are not accepted, and reservations are required for all visitors. Lodging is also available on-site, and the standard private room rate includes a morning tour and unguided access to the park, the latter a perk not offered to day visitors.

This nature-themed adventure park—complete with a canopy tour and hanging bridges—is just outside the Santa Elena Reserve. An enclosed 20-species mariposario (butterfly garden), a sloth sanctuary, a herpetario (frog and reptile house), and insect exhibition are located near the visitor center. The only zip line tour built entirely inside the Monteverde Cloud Forest has 12 lines through the misty canopy and 18 platforms, with an optional Tarzan swing at the end to round out the excursion. The Tree Top Walkway takes you to heights ranging from 36 feet up to 180 feet on a 3-km (2-mile) walk. These are some of the longest and strongest bridges in the country and run through the same canopy terrain as the zip line tour, which sometimes makes for a not-so-quiet walk.

You can choose from numerous mix-and-match packages, depending on which activities interest you, or take it all in, with lunch included, for $169. Most visitors get by for much less, given that one day isn't enough for all there is to do here.

A small ecotourism project outside town exhibits 60 species of medicinal plants, abundant animal life—including sloths and caimans—and butterfly and orchid gardens. This is a great place to see Costa Rica's famed red poison dart frogs up close. You can also learn about the indigenous Maleku culture and see their art displayed. Seven guided tours are offered daily from 8 am to 3:30 pm. A two-hour guided evening tour begins at 5:45 and should be reserved in advance, or you can get a self-guided day pass. The center can arrange your transportation, too.