The underground river is known as one of the Worlds 7 wonders of Nature. It is a UNESCO World heritage site. Puerto Princesa City Subterreanean River National Park is a World Heritage Site inscribed by UNESCO on December 4, 1999. The Worlds Longest Navigable Underground River and Now one of the & Wonders of Nature.     The primary tour destination PPUR has the worlds navigable Underground river with its spectacular rock stalactites and stalagmites formation that made it to be among the UNESCO WORLD HERITAGE SITE and awarded as RAMSAR site.