Longest duration at full ocean depth by a crewed vessel
Hamish Harding, Victor Vescovo
4 hours 15 minutes hour(s):minute(s)
Not Applicable ()

The longest time spent traversing the deepest part of the ocean on a single dive is 4 hours 15 minutes by Hamish Harding (UK) and Victor Vescovo (USA), who travelled 4.634 km (2.88 miles) along the sea floor of Challenger Deep in the Mariana Trench in the Deep-Submergence Vehicle (DSV) Limiting Factor on 5 March 2021.

Challenger Deep is located about 300 km (186 mi) south-west of Guam in the western Pacific Ocean and is the deepest point in the ocean, with a depth in its "Eastern Pool" of c. 10,930 m (35,860 ft).

Harding's dive with Vescovo (who built the DSV Limiting Factor)was the longest in terms of the time spent at "full ocean depth" and the distance covered during their traverse at the bottom.