An incomparable once-in-a-lifetime experience, this adventure offers up nature’s breathtaking beauty and mysteries above and below the earth’s surface. Vietnam’s uniquely complex and ancient karst ecosystem has created astounding formations including underground rivers, caves and jutting mountainous rock formations on land and water, all of which you will experience on this journey. Traversing the jungle, scaling mountainous paths, crossing rivers both above and underground, you will descend into the astounding bowels of the earth for an otherworldly experience. Underground in the largest cave system in the world, you can also relax and experience the peace and tranquility of complete silence with no intrusions.