Tree House Lodge, Limón, Costa Rica

Within the Gandoca-Manzanillo Wildlife Refuge on Costa Rica’s Caribbean coast, this collection of four eco-friendly villas—only one of which is actually a tree house—occupies a ten-acre property between the golden sands of Punta Uva beach and thick rainforest. Between March and May, leatherback and green sea turtles come ashore here to lay eggs; the trees are home to coatimundi, howler monkeys and two- and three-toed sloths. The tree house, accessible by a swooping suspension footbridge, is bi-level, airy and built entirely of local sustainable hardwoods; it has two bedrooms, a kitchen and dining area and an extraordinary lower-level bathroom through which the trunk of a century-old, living Sangrillo tree winds. All the spaces are enclosed by wide windows that are screened but, otherwise, open to nature. From $300; costaricatreehouse.com.