This trek is perfect for those with little hiking background but want to get a true jungle and cave experience. It begins deep in the jungle of Phong Nha Ke Bang National Park, Vietnam. You’ll take a short hike to the impressive Elephant Cave, then a walk through Ma Da Valley to the amazingly blue waters of Crystal Ma Da Lake. After lunch and swimming, you’ll continue trekking to Tra Ang Cave were everyone will gear up to swim into the furthest reaches of the cave.