Lapas Nest Tree House, Puerto Jimenez, Costa Rica

Fall asleep to the sounds of monkeys (hopefully, not the howler monkeys) and birds in the private Sombra de Lapa rainforest, a reserve on the Osa Peninsula. A spiral staircase leads to the house, which is more than 55 feet high and built around a Guanacaste tree. It has six levels, four bedrooms and two baths (one has a glass-bottom shower), as well as clear roof panels so you can see the Congo and White Face monkeys in the trees. The house has modern amenities and a spring-fed dipping pool in the rainforest.

Price: $200 per night. Minimum three night-stay. Sleeps 8.