Boybuloq Cave
The cave is the deepest known cave in Asia having been explored to a depth of from the entrance. At the lowest discovered level a water-filled siphon blocks further exploration. It is thought that the cave has the potential to be the deepest known cave in the world, with a theorised depth of making it deeper than the Veryovkina Cave. The explored length of the cave is .
Xe Bang Fai River
Xe Bang Fai River Cave, also known as Khoun Xe Cave (Tham in Laotian is "Cave"), is an immense river cave located in a remote corner of Khammouane Province. It is believed to be one of the largest river cave in the world with enormous passages some 120 meters tall and 200 meters wide, and subterranean channel 7 km long.