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 .
Vorontsovka Caves
The Vorontsovskaya Cave System (Воронцовская система пещер) is a long chain of caves in the Khosta and Adler districts of Sochi, Russia. It is part of a range of Mesozoic limestones that runs parallel to the Black Sea coast for 400 km. and contains the Voronya Cave, the world's deepest cave.