Nominated and included in the top 28 finalist for the "New Seven Wonders of Nature" competition. It was inscribed by UNESCO as a World Heritage Site on December 4, 1999.
The Puerto Princesa Subterranean River National Park is located about 50 kilometers north of the city of Puerto Princesa, Palawan, Philippines. It features a limestone karst mountain landscape with an 8.2 kilometer navigable underground river.
The National Park is located in the Saint Paul Mountain Range on the
northern coast of the island. It is bordered by St. Paul Bay to the
north and the Babuyan River to the east. The City Government of Puerto
Princesa has managed the National Park since 1992. It is also known as
St. Paul's Subterranean River National Park, or St. Paul Underground
River. The entrance to the Subterranean River is a short hike from the
town of Sabang.
A distinguishing feature of the river is that it winds through a cave before flowing directly into the South China Sea. It includes major formations of stalactites and stalagmites, and several large chambers. The lower portion of the river is subject to tidal influences. Until the 2007 discovery of an underground river in Mexico's Yucatan Peninsula, the Puerto Princesa Subterranean River was reputed to be the world's longest underground river.
The area also represents a habitat for biodiversity conservation. The site contains a full mountain-to-the-sea ecosystem and has some of the most important forests in Asia. At the mouth of the cave, a clear lagoon is framed by ancient trees growing right to the water's edge. Monkeys, large monitor lizards, and squirrels find their niche on the beach near the cave.