Challenger Deep
The Challenger Deep in the Mariana Trench is the most profound realized point in Earth's seas. In 2010 the United States Center for Coastal and Ocean Mapping estimated the profundity of the Challenger Deep at 10,994 meters (36,070 feet) underneath ocean level with an expected vertical exactness of ± 40 meters.
The Challenger Deep is having such profundities that even the Mt. Everest would be secured by over a mile of water if it's put in there.
The latest estimation, done in 2010, is the 10,994 meter ( ± 40 meter exactness) whearas the principal profundity estimations done by the British review dispatch HMS Challenger in 1875 asserted the profundities to be 8,184 meters (26,850 feet).