The vast Vieng Xai Caves were used as a bomb shelter during the 1964-1973 American Secret War, eventually becoming a subterranean city that housed over 20,000 people. The surrounding limestone mountains are gorgeous, and the cave tours are outstanding, making this one of Laos' best kept secrets.
Kaysone Phomvihane Cave
Kaysone Phomvihane became Laos’ first prime minister after surviving the war, and this large cave was his home. Features include the Politburo meeting room, where leaders of the Pathet Lao regularly met over a large table, as well as an airtight bomb shelter room complete with a Russian air pump to keep inhabitants from asphyxiating.
Prince Souphannouvong’s Cave
This cave features multiple meeting rooms and sleeping areas. It’s set high up in a cliff and surrounded by chopped off rock faces and bomb craters – it was bombed repeatedly as Souphannouvong, known as the "Red Prince," due to his ties with Vietnam, was seen as a prominent figurehead of the Pathet Lao with his royal family background.
Prince Souphannouvong’s Garden
Much of the terrain surrounding the caves has been planted with vivid red Coleus plants red, chosen as a mark of the bloodshed caused by the war. This garden, which fronts the entry to the Prince’s cave, is particularly poignant; the red plants contrast with the mossy green walkway leading up to the cave, along with a vast orchard of pomelo trees maintained by the Prince, who built his home here following the end of the bombing. Check out the fountain full of fish, which will come swimming up if you clap your hands. On closer inspection, you’ll see that the fountain is built in a former bomb crater.
Hospital Cave
While this wasn’t the main hospital (it was in a massive cave 7km from the main cave site and is no longer visitable), this small cave was used as a treatment facility during bombings when patients couldn’t reach the larger facility. There were operating rooms built inside, and even Cuban doctors came here to assist during the war. A pair of lone crutches are pretty much all that’s left here, but just glancing around at the location and conditions will make you both shudder and be awed by what the cave dwellers survived and were able to accomplish.
Artillery Cave
Set high up on the edge of a cliff, this cave was used as the defense post thanks to its position looking out at the valley, where soldiers could spot incoming planes. The cave was stocked with anti-aircraft artillery and guns and used to defend the cave complex as a whole. It’s a long climb up slippery stairs to reach this area, and thus it’s sometimes omitted from the tour during the rainy season.
Khamtay Siphandone’s Cave
This series of caves is visually striking, with some great stalactite formations. They were used as both soldiers' barracks housing up to 2000 troops, and the communications center complete with a printing cave, radio station and telegraph office. Especially poignant is the children's bedroom – one of the boys who slept there is Sonexay Siphandone, current prime minister of Laos!
Xanglot Cave
They fittingly save this huge cave for the end of the tour. With its enormous open space, it was used for rallies and assemblies, as well as weddings, film screenings and theater performances. The ideological documentary The 17th Parallel about the Second Indochina War and DMZ was the most popular movie, and was shown weekly here for years.
