Which Philippine national park is a UNESCO site known for its underground river?

Puerto Princesa Subterranean River National Park is the Philippine national park known for its UNESCO-listed underground river.

The park lies in the Saint Paul Mountain Range on Palawan’s western coast, roughly 80 kilometers north of Puerto Princesa. Its centerpiece is the Puerto Princesa Subterranean River, an underground section of the Cabayugan River that passes through a limestone cave system before reaching the South China Sea.

The navigable river extends about 8.2 kilometers underground, although visitor boat trips cover only part of that distance. Saltwater reaches deep into the cave, creating an underground estuary where freshwater and seawater interact. The surrounding park protects a mountain-to-sea ecosystem containing forests, coastal habitats, caves, and rich Palawan wildlife.

UNESCO inscribed the site as a World Heritage Site in 1999. It was also named one of the New7Wonders of Nature in 2012. Visitors generally reach the river from Sabang and continue by boat. Banaue Rice Terraces and Tubbataha Reefs are major Philippine attractions, but neither is the underground-river national park described here.