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 .
Velebit caves
The vertical shaft "Patkov Gušt", named after a deceased Croatian speleologist is 553 meters deep and the second deepest pitch in the world .