US-US adventurer Victor Vescovo has become the first person to visit the deepest points in every ocean.

His fifth and final dive in a prototype submersible was made to the bottom of the Arctic’s Molloy Trench, some 5.5km (3.4 miles) below the sea surface.

This followed dives during the past 10 months to the floor of the Pacific, Indian, Southern and Atlantic oceans. The millionaire financier’s team also visited the wreck of the Titanic.

All Vescovo’s dives were made using the 12-tonne Deep Sea Vehicle (DSV) Limiting Factor, launched and recovered from a dedicated support ship, the DSSV Pressure Drop, ironically a one-time navy submarine hunter.

The recorded depth on the solo dive was 5,550m, plus or minus 14m. It is the first time any human has been to this location.

Vescovo spoke of his elation and deep gratitude to the people who had worked with him.

“These things need to be done,” he told BBC News. “I come from a philosophy that says we’re put here not just to survive, or even just to be comfortable - but to contribute in some way. And the path I chose was to have some adventure whilst also doing something that could move us forward as a species.”