Sabang - Palawan - Philippines

Sabang is a small village in Palawan. It is used as an entry point to the Puerto Princesa Subterranean River National Park. The river is also called Puerto Princesa Underground River.

The national park is located in the Saint Paul Mountain Range on the western coast of the island. The City Government of Puerto Princesa has managed the National Park since 1992. The entrance to the subterranean river is a short hike or boat ride from the town Sabang.

The park has a limestone karst mountain landscape. St. Pauls Underground River Cave is more than 24 km long and contains an 8.2 km long underground section of the Cabayugan River. The river winds through the cave before flowing directly into the West Philippine Sea and is navigable by boat up to 4.3 km in from the sea. The cave includes major formations of stalactites and stalagmites, and several large chambers, including the 360-meter-long Italian's Chamber with approximate 2.5 million square meters volume. It is one of the largest cave rooms in the world.

Until the 2007 discovery of an underground river in Mexico's Yucatán Peninsula, the Puerto Princesa Subterranean River was reputed to be the world's longest underground river.