Take a 3-hour ride from Hue to Phong Nha Cave. On the way we stop to visit some of the most famous battle-field in the Vietnam War, Ben Hai River, Hien Luong Bridge, lying in the Demilitarized Zone of the Vietnam War. The bridge is located right on the 17th parallel, crossing the Ben Hai River at the section running through Hien Luong Village, Vinh Thanh Commune, Vinh Linh District, Quang Tri Province, Central Vietnam. During the 21 years of the Vietnam War, from 1954 to 1975, Hien Luong Bridge was the boundary dividing Vietnam into two regions: the North managed by the Democratic Republic of Vietnam and the South by the Republic of Vietnam..Have lunch at a local restaurant then get on boat and cruise along the river to Phong Nha Cave which is designated as Unesco World Heritage Site in 2003. The deeper one penetrates, the more magical are the natural aspects of the caves. After that, you will take a 25-minute ride to the water cave walk to discover the dry cave for 500m more. You will have a chance to explore the remain of Cham Altars and Inscriptions inside.