Phong Nha-Kẻ Bàng National Park, a UNESCO World Heritage Site, is a very recent addition to the must-see places in Vietnam. In 2005 a local man was searching the mountainside for medicinal herbs and discovered Paradise Cave, which stretches for 31 kilometers (19 miles) below the mountain. Opened to the public in 2010, tourists generally get to see the first kilometer, with further depths restricted to more serious spelunkers.
