Bathyscaphe Trieste
Trieste is a Swiss-designed, Italian-built deep-diving research bathyscaphe, which with its crew of two reached a record maximum depth of about , in the deepest known part of the Earth's oceans, the Challenger Deep, in the Mariana Trench near Guam in the Pacific. On 23 January 1960, Jacques Piccard (son of the boat's designer Auguste Piccard) and US Navy Lieutenant Don Walsh achieved the goal of Project Nekton.
Challenger Deep
The 2009 and 2010 maximal depths were not confirmed by the series of dives "Nereus" made to the bottom during an expedition in May–June 2009. The direct descent measurements by the four expeditions which have reported from the bottom, have fixed depths in a narrow range from () to (), to ("Nereus") to () Although an attempt was made to correlate locations, it could not be absolutely certain that "Nereus" (or the other descents) reached exactly the same points found to be maximally deep by the sonar/echo sounders of previous mapping expeditions, even though one of these echo soundings was made by "Nereus" mothership.