Manuel Antonio, Costa Rica
Arenas del Mar is proof that staying at an eco-resort doesn't mean roughing it: Its 38 contemporary rooms are among the nicest in Manuel Antonio, its restaurant is excellent, and its public spaces embody rustic luxury. The hotel went to great lengths not to disrupt the surrounding ecosystem, so wildlife sightings are a daily occcurence. Before constructing the hotel, developers studied the native monkeys and built in areas that wouldn't interfere with their daily routes. And it's not just the design that's eco-friendly: Initiatives such as solar panels, an underground electricity system, and chlorine-free ionization system in the pools allow the resort to respect the environment in its daily operations.