What is the name of the world’s deepest known ocean trench?

The Mariana Trench is the world’s deepest known ocean trench.

It lies in the western Pacific Ocean, east of the Mariana Islands, where the Pacific Plate descends beneath the Mariana Plate. Its deepest known point is Challenger Deep, which reaches roughly 10,900 metres below sea level, although exact figures vary among surveys and instruments.

The trench is part of a subduction zone, a boundary where one tectonic plate moves beneath another. This process creates deep ocean trenches and contributes to earthquakes and volcanic activity in the surrounding region.

The first crewed descent to Challenger Deep took place in 1960, when Jacques Piccard and Don Walsh reached the bottom in the bathyscaphe Trieste. Film director James Cameron made a solo descent in 2012. The trench is deeper than Mount Everest is tall.