Caño Island Biological Reserve: Snorkelers' Paradise

Most of uninhabited 2½-square-km (1-square-mile) Caño Island Biological Reserve is covered in evergreen forest that includes fig, locust, and rubber trees. The indigenous Diquis tribe used the island as a ceremonial and burial site until the Spanish arrived, and the numerous bits and pieces unearthed here have prompted archaeologists to speculate about pre-Columbian long-distance maritime trade. But virtually none of these indigenous artifacts remain. The main attraction is the ocean around the island, offering advanced scuba diving and snorkeling. The snorkeling is best around the rocky points flanking the island's main beach; if you're a certified diver, you'll want to explore Bajo del Diablo and Paraíso, where you're guaranteed to encounter thousands of good-size fish, and if you’re lucky, white-tip, nurse, and trigger sharks. As of this writing, visitors are once again allowed to land on the island, to hike a trail that climbs to the island’s summit. But no picnicking is allowed on the beach, and there are no toilet facilities, owing to runoff that was damaging the surrounding coral.

The only way to get to the island, 19 km (12 miles) due west of the Osa Peninsula, is by boat, arranged by your lodge or a tour company. Reserve well ahead, since tour operators have to keep to specific time limits and visitor quotas of 200 visitors per day, split between morning and afternoon. Drake Bay hotels run trips here, as do tour companies in Dominical, Uvita, and Sierpe.