The Puerto Princesa Subterranean River National Park also known as St. Paul Subterranean River is located in the Saint Paul Mountain Range on the west coast of Palawan and 81 km northern coast of the Puerto Princesa. Declared as a national park in 1971, the land forms in this 3,901 ha of park are connected by rocky mountains running from north to south. The forest ecosystem has a momentous habitat for biodiversity conservation. Its underground river serves as a home to other cove dwelling fauna. The forest houses numerous numbers of endangered endemic species such as the Palawan tree shrew, Palawan porcupine, Palawan stink badger, Palawan Pheasant Peacock and Philippine Cockatoo. Numerous monitor lizards and marine turtles are seen in the area. The park has luxuriant mangroves, mossy forest, sea grass beds as well as coral reefs
Its geographical feature is truly amazing. There is a limestone karsts mountain landscape with an 8.2 km with the long navigable underground river known as Cabayugan River, which winds through a 15 km St. Paul Subterranean, there one can have a glimpse of cathedral like caverns and domes before flowing directly into the South China Sea. Through the cave are several large chambers and wonderful formation of stalactites and stalagmites that houses large numbers of swiftlets and bats.