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.
Actun Box Ch'iich'
At -183m, Actun Box Ch'iich' (Cave of the Black Birds) is the deepest cave in the country of Belize. Located above Roaring Creek in the Cayo District, it is one of several caves explored and documented by British and Canadian cavers during a three-week expedition in 1989. The cave contains a small stream and has both an upper and lower entrance, making a through-trip possible.