The Puerto Princesa Underground River (PPUR) has placed Palawan in the forefront of tourism after it was hailed as one of the new seven wonders of Nature. The 8.2-kilometer subterranean river runs under a protected cave that features spectacular formations of stalactites and stalagmites. With these and its limestone landscape, it is considered as one of the world’s most complex cave systems. You’ll have an incredible experience exploring the caves of Underground River. Plus, you’ll probably enjoy the many quirky jokes care of your friendly boatman/tour guide.