The Underground River, or as it is officially named, the Puerto-Princessa-Subterranean-River-National-Park, is a UNESCO World Heritage Site and also among the New 7 wonders of the World. Alongside the Amazon, Halong Bay or Iguazu Falls, the Underground River finds itself in famous company. With its about 8,2 kilometers, the Underground River is one of the longest of its kind. A bit confusingly, the river is actually located near the sleepy village of Sabang and not close to Palawan's capital Puerto Princessa, as the name might suggest. From Sabang you can take a tour which will take you deep inside the cave to explore this natural wonder. A guide will row your outrigger canoe along the calm river and into the dark. You will be able to see monstrous stalagmites and stalactites, caves as big as cathedrals, little waterfalls and colonies of bats and swifts living inside. The fact that the boats use no motors makes for an almost enlightening experience. It is something you don't want to miss when in Palawan.