Where is the Mariana Trench?
Quick answer
The Mariana Trench is in the western Pacific Ocean, east of the Mariana Islands and near Guam. It contains the deepest known point in Earth’s oceans, the Challenger Deep, about 10,935 meters (35,876 feet) below sea level. That’s deeper than Mount Everest is tall.
Key facts
- Ocean
- Western Pacific
- Deepest point
- Challenger Deep, ~10,935 m (35,876 ft)
- Length
- About 2,550 km (1,580 miles)
- Protected
- Part of the Marianas Trench Marine National Monument (US)
How deep is it?
If you dropped Mount Everest (8,849 m) into the Challenger Deep, its peak would still be more than 2 km underwater. Depth measurements vary slightly, from about 10,900 to 11,000 m, depending on the equipment used.
How did it form?
The trench is a subduction zone. The heavy, older Pacific Plate slides beneath the smaller Mariana Plate, bending down into Earth’s mantle and creating a deep, crescent-shaped valley in the seafloor.
Who has been to the bottom?
- 1960Jacques Piccard and Don Walsh reach the Challenger Deep in the bathyscaphe Trieste
- 2012Filmmaker James Cameron makes the first solo dive in the Deepsea Challenger
- 2019Explorer Victor Vescovo completes several dives in the submersible Limiting Factor
- 2020sDozens more people, including the first women, have now visited the deepest point
Life in the deep
Even at the bottom, in complete darkness and near-freezing water, with pressure more than 1,000 times that at sea level, scientists have found amphipods (shrimp-like creatures), sea cucumbers, microbes and, a little higher up, the Mariana snailfish, one of the deepest-living fish known. Sadly, researchers have also found plastic bags at the bottom.
The ocean is vital to life on land too; read why the ocean is important. For more ocean extremes, see which country has the longest coastline.
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