Vietnam, a rather poor asian country is famous for the Vietnam war in the middle of the 20th century (locally called American War). After the Americans lost the war, the country became socialist and was not reachable for western toursists. Now, after the cold war, the country becomes open to tourists. They are rather welcome, as they bring money to the poor country, still traveling has some difficulties and restrictions.
As other countries in this area, Vietnam has a lot of karst with many caves. Still there is no well developed infrastructure, and thus no set of well developed show caves.
Much more important are the caves which played a role in the Vietnam War. Natural and even more often artificial caves were used as air raid shelter, as bunker, or as hideout. Some of the artificial caves were opened to tourists lately. It seems they widened the extremely narrow and low tunnels to fit the size of American tourists. Finally money obtained what napalm could not.
The president of Viet Nam's Association of Caves and Grottoes is Prof. Dr. Nguyen Quang My. He is also the head of the Department of Geography and Geology, College of Natural of Science at the Ha Noi National University. He wrote various publications about caves, especially show caves.