Than Nam is a flooded cave system a short way outside of Vang Vieng. It is best visited as part of a tour as you are unable to enter  without a guide. The cave system is explored while sitting in a rubber  ring which you are able to move by pulling yourself along a series of ropes tied throughout the caves.

This is defenitely not a cave system to be visited if you suffer from claustrophobia however, particularly during the wet season when the water levels are higher as there are parts of the cave where you will be expected to pull yourself through gaps that slim people will barely fit through.

As part of a tour the eating area outside the cave is usually  used as a lunchtime stop off point. It is useful to keep some smaller Laotian currency with you while visiting these caves as there is a 1,000 Kip charge for using the toilet outside the caves.