11.03 Kms (6.85 mi)
The Mariana Trench or Marianas Trench is the deepest part of the world's oceans. It's located in the western Pacific Ocean, to the east of the Mariana Islands. The trench is about 2,550 kilometers (1,580 mi) long but has an average width of only 69 kilometers (43 mi). It reaches a maximum-known depth of 10.911 km (10,911 ± 40 m) or 6.831 mi (36,069 ± 131 ft) at the Challenger Deep, a small slot-shaped valley in its floor, at its southern end, although some unrepeated measurements place the deepest portion at 11.03 kilometers (6.85 mi).
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