Centro Ecologico Sian Ka’an (CESiaK), Mexico
Close to the Mayan ruins of Tulum on the Yucatan Peninsula is the Sian Ka’an Biosphere Reserve, a UNESCO World Heritage Site and the largest protected area on the Mexican Caribbean. Grab one of the raised cottages on site and you’ll be immersed in the 1.3 million-acre mix of beach and wetlands. CESiaK runs completely on sun and wind energy, using rainwater for water needs, and utilizing a wetland waste treatment system. Grab a sea kayak to go bird watching, fish, go with a naturalist on a hike, or simply relax with a thick book in the hammock. All proceeds fund education and conservation programs at Sian Ka’an, including dune restoration and native plant propogation. Cabins start at an affordable $70 a night.