They then give a list of 25 'top' destinations (which are debatable!) - eg's being: .
1. Alonissos: Alonissos’ National Marine Park is home to the endangered monk seal and lots of other interesting species of wildlife. It’s environmentally protected and has status as one of The European Community’s six “ECO Islands.” A number of Alonissos rentals are electricity-free.
2. The Lodge at Chaa Creek: This 330-acre ecoresort is located in western Belize on the banks of the Macal River. Resort activities are focused around the environment, culture, and archaeology of Belize. You’ll be able to explore the river, hike, watch birds, go mountain biking, and more. This resort has won the Conde Nast Traveler’s Ecotourism Award.
3. Maho Bay: One of the world’s first ecoresorts, Maho Bay Camp is built on 14 acres of gorgeous land. This simple inn by the water uses boardwalks to preserve trees and brush and other strategies for treading lightly. Because of this, the 100 units that make up the camp are nearly invisible.
Read in full - 'EcoTripping: 25 Vacations for Green Travelers'