Boybuloq Cave
Boybuloq Cave (also known as Boy Bulok) is a limestone cave in Uzbekistan and the deepest known cave in Asia. It is located high in the Gissar Range of mountains, near to Dehibolo, Uzbekistan's highest village. The cave and wider area is inaccessible for much of the year due to snow. Long-known to local people because of a nearby spring the cave was first explored by speleologists in 1984. Since then expeditions have mapped of passages in the cave and reached a total depth of . The cave could potentially extend much deeper and become the deepest in the world.
Blauhöhle
The Blauhöhle is the largest cave system in the Swabian Alps in southern Germany. The Blauhöhle presumably originated in a time when the Danube still flowed through the Blau valley. Since the shifting of the Danube, several small rivers, the Schmiech, the Ach, and the Blau, have flowed through this valley. The cave system begins about 21 meters under water at the base of the Blautopf. It continues west and northwest, rising and falling several times until after a horizontal distance of about it comes above the level of ground water and opens into the second big air-filled chamber. The maximum depth of the cave under water is .