
Phong Nha-Ke Bang National Park contains the oldest major karst area in Asia. Protecting those caves is the reason for the park and also why it was named a UNESCO World Heritage Site. This cave is called Thien Duong (Động Thiên Đường) and is over 19 miles (31 km) long. The British cave explorers were so impressed by the beauty of the rock formation inside the cave, they dubbed this place as “Paradise Cave.” Photo #1 by Vo Thanh Lam