Vieng Xai is a district and town in Hua Phan Province. The town is located on Route 6, 30 Km from Sam Neua (Province capital) and 55 km from the Vietnam/Laos border in Na Meo. The biggest attraction of the town are the caves. The former Pathet Lao headquarters of Vieng Xai sit in a striking valley of fertile hills and limestone cliffs riddled with caves, several of which were used to shelter the Pathet Lao officers during the second indo-china war.
The Pathet Lao moved east to Vieng Xay and these limestone karst cave networks sheltered their headquarters during their struggle with the American-backed Royal Lao Government. In these caves the Pathet Lao established a “Hidden City” which supported around 20,000 people. During nine years of almost constant bombing, they sheltered in caves and surrounding jungle. Most of their daily lives were led under cover of darkness. Schools, hospitals and markets as well as government ministries, a radio station, a theatre and military barracks were all hidden in the caves.