The Mariana Trench or Marianas Trench is located in the western Pacific Ocean about 200 kilometers (124 mi) east of the Mariana Islands; it is the deepest oceanic trench on Earth. It is crescent-shaped and measures about 2,550 km (1,580 mi) in length and 69 km (43 mi) in width.

The maximum known depth is 10,984 meters (36,037 ft) (± 25 meters (82 ft)) (6.825 miles) at the southern end of a small slot-shaped valley in its floor known as the Challenger Deep. However, some unrepeated measurements place the deepest portion at 11,034 meters (36,201 ft). If hypothetically Mount Everest were placed into the trench at this point, its peak would still be under water by more than two kilometers (1.2 mi).

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