The Mariana Trench
The Mariana Trench is the deepest known part of the world's oceans, and the lowest elevation of the surface of the Earth's crust. It is located in the western Pacific Ocean, to the east of the Mariana Islands. The trench is about 2,550 kilometres (1,580 mi) long but has a mean width of only 69 kilometres (43 mi). It reaches a maximum depth of about 10,916 metres (35,814 ft) at the Challenger Deep, a small slot-shaped valley in its floor, at its southern end.
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