"On the Dominican Republic ’s southeastern coast, near Bayahibe, this 300-square-mile UNESCO World Heritage site spans both land and sea. As you snorkel or row a glass-bottom boat out to one of the three islands in the reserve—Saona (a turtle nesting site from March through November), Catalina, and Catalinita—be on the lookout for bottlenose dolphins, manatees, four species of sea turtles, and, from January through March, humpback whales. You can also hike the Sendero del Padre Nuestro trail to explore caves filled with well-preserved Taino pictographs, or try to spot some of the 144 bird species that call the park home, from white-headed doves and red-footed boobies to barn owls and Hispaniolan parrots. There’s even a frigate bird colony at Bahia de las Calderas."