Hai Van Mountain is the natural boundary between Thua Thien-Hue Province and Da Nang City. Hai Van Mountain is majestic and poetic. The peak looks far into the sea. Two sentry towers along the pass, with one left by French colonists and the other by American troops during the Vietnam War, seem to tell a detailed account of Vietnam's two sad histories. The winding mountain highway of Hai Van Mountain and Lang Co Bay along the road have been selected by National Geographic magazine as one of must-go places in life.