Bathyscaphe Trieste
On 23 January 1960, she reached the ocean floor in the Challenger Deep (the deepest southern part of the Mariana Trench), carrying Jacques Piccard and Don Walsh. This was the first time a vessel, manned or unmanned, had reached the deepest known point of the Earth's oceans. The onboard systems indicated a depth of , although this was revised later to ; fairly recently, more accurate measurements have found Challenger Deep to be between and deep.
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.