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.
Pierre Chevalier (caver)
Pierre Chevalier (24 April 1905 – 4 December 2001) was a well-known caver and mountaineer from France, with many alpine ascents and cave explorations to his credit. Chevalier is principally known for the exploration of the Dent de Crolles cave system over a twelve-year period (1936 – 1947), which became the deepest cave in the world. Chevalier recorded this exploration in his book "Escalades souterraines" ("Subterranean Climbers").