Bathyscaphe Trieste

Trieste was a Swiss designed deep-diving research bathyscaphe ("deep boat") with a crew of two people, which reached a record-breaking depth of about 10,900 m (about 35,760 ft), in the deepest part of any ocean on earth, the Challenger Deep in the Mariana Trench, in 1960. The dive has never been repeated, and presently no manned or unmanned craft exists capable of reaching such depth.
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