<P> Coordinates: 11 ° 21 ′ N 142 ° 12 ′ E ﻿ / ﻿ 11.350 ° N 142.200 ° E ﻿ / 11.350; 142.200 </P> <P> The Mariana Trench or Marianas Trench is located in the western Pacific Ocean approximately 200 kilometres (124 mi) east of the Mariana Islands, and has the deepest natural point in the world . It is a crescent - shaped trough in the Earth's crust averaging about 2,550 km (1,580 mi) long and 69 km (43 mi) wide . The maximum known depth is 10,994 metres (36,070 ft) (± 40 metres (130 ft)) 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 metres (36,201 ft). For comparison: if Mount Everest were dropped into the trench at this point, its peak would still be over 2 kilometres (1.2 mi) under water . </P> <P> At the bottom of the trench the water column above exerts a pressure of 1,086 bars (15,750 psi), more than 1,000 times the standard atmospheric pressure at sea level . At this pressure, the density of water is increased by 4.96%, so that 95.27 litres of water under the pressure of the Challenger Deep would contain the same mass as 100 litres at the surface . The temperature at the bottom is 1 to 4 ° C (34 to 39 ° F). </P>

What part of the ocean is the deepest