What is the name of the deepest point in the Mariana Trench?

The deepest point in the Mariana Trench is called Challenger Deep. It is the deepest known point on Earth's seabed, lying in the western Pacific Ocean at the southern end of the Mariana Trench.

Challenger Deep is not a separate trench; it is a slot-shaped depression within the much larger Mariana Trench. Modern surveys place its maximum depth at roughly 10,900 to 11,000 meters below sea level, though the exact figure varies with instruments, sound-speed calculations, and the basin measured.

The feature was first detected during the 1872–1876 voyage of HMS Challenger, one of the earliest major scientific oceanographic expeditions. Its name honors that ship and the later HMS Challenger II survey, which confirmed the exceptional depth using echo sounding.

In January 1960, Jacques Piccard and Don Walsh became the first people to reach the bottom in the bathyscaphe Trieste. James Cameron made the first solo descent in 2012, and later expeditions expanded measurements of Challenger Deep's western, central, and eastern basins.