Vieng Xai (also Vieng Xay, Vieng Sai) is a district and town in Hua Phan Province. The town is located on Rte 6, 30 km from Sam Neua (provincial capital) and 55 km from the Vietnam/Lao border in Na Meo.

The biggest attraction of the town is the caves. The former Pathet Lao (PL) Revolutionary 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 PL officers during the second Indochina War.

During the 1960s, political developments in Laos were influential in the future of this whole region. The US believed that Laos was crucial in the prevention of communist expansion, so this small country became caught up in the conflict between the US and the North Vietnamese. In 1964, the US began intensive bombing of the Lao communist movement’s, Pathet Lao, base area in Xieng Khouang. The Pathet Lao moved east to Vieng Xay and these limestone karst cave networks sheltered their headquarters during their struggle with the US-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 the surrounding jungle. Most of their daily lives was conducted under cover of darkness. Schools, hospitals, and markets as well as government ministries, a radio station, a theater, and military barracks were all hidden in the caves.

In 1973 a ceasefire stopped the bombing and the new town of Vieng Xay was established as the capital of the liberated zone. On the 2 Dec 1975, the Lao People’s Democratic Republic was declared, and the capital city was transferred to Vientiane.