Puerto Princesa Subterranean River National Park

This national park protects the Puerto Princesa Subterranean River on the island of Palawan in the Philippines, within the Saint Paul Mountain Range about 80 kilometers north of Puerto Princesa city. Its centerpiece is an 8.2 kilometer navigable underground stretch of the Cabayugan River running through a cave system at least 32 kilometers long and emptying directly into the South China Sea, making it one of the longest underground rivers in the world. The park protects a complete mountain to sea ecosystem, hosting 165 recorded bird species, about two thirds of Palawan's bird fauna, and 30 mammal species, alongside cave formations that include one of the largest single cave chambers known. It has been recognized as a UNESCO World Heritage Site, a Ramsar wetland of international importance, and one of the New7Wonders of Nature.