The Deepest Part on the Earth – Mariana Trench
The Deepest spot on the earth is the Mariana Trench , which is located at the western Pacific Ocean.
It’s depth below sea level is 10,994 m (± 40 m)or 36,070 ft ±( 131 ft).
The sea floor of this spot is known as Challenger deep. If The highest Mountain ,The Mount Everest would be placed in it , it would be covered by seawater and sea level would be approx 1 mile above the Mount .
In 2012 James Cameron achieved the milestone of reaching the floor of Challenger Deep.Below is the Short video of James Cameron, self describing the summary of the Ocean depth.