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 .
Endless Caverns
The present mapped extent of Endless Caverns is , making it the 20th longest cave in Virginia and the 176th longest in the United States. Its deepest measured point is below the surface.