China livestreamed footage of its new manned submersible parked at the bottom of the Mariana Trench on Friday, part of a historic mission into the deepest underwater valley on the planet.

The “Fendouzhe”, or “Striver”, descended more than 10,000 metres (about 33,000 feet) into the submarine trench in the western Pacific Ocean with three researchers on board, state broadcaster CCTV said.

Only a handful of people have ever visited the bottom of the Mariana Trench, a crescent-shaped depression in the Earth’s crust that is deeper than Mount Everest is high and more than 2,550 kilometres (1,600 miles) long.