"Avatar" director James Cameron made a solo dive this weekend to the deepest part of the ocean and found a world that felt "desolate," "foreboding" and "moon-like."

In a daring expedition, the Canadian-born filmmaker travelled to the Mariana Trench -- the deepest part of the ocean.

Cameron is the third man in history to complete the 11-kilometre dive to the Mariana Trench, known as the lowest part of the ocean floor.

Cameron is also the first person to make the trip alone to this trench which covers an area 120 times larger than the Grand Canyon and nearly two miles deeper than the height of Mount Everest.

The journey inside the submarine Sea Challenger left Cameron visibly awed as he spoke with the media early Monday morning in a phone press conference.

"I was on the bottom, I honestly haven't even added it up but it must have been about five hours," Cameron, 57, told reporters.

Cameron later clarified that he was at the bottom of the ocean floor for a little more than two-and-a-half hours, and had to cut short his planned six-hour stay because of problems with the submarine's hydraulics system.

Even so, Cameron described the rare view as a "gelatinous featureless plane" that went on almost as far as the eye could see.

This National Geographic Explorer-in-Residence explorer also called this adventure the culmination of "a lifelong dream."

"There had to be a moment where I just stopped, and took it in, and said, 'This is where I am; I'm at the bottom of the ocean, the deepest place on Earth. What does that mean?"' Cameron told reporters after journeying nearly seven miles below sea level.

"I just sat there looking out the window, looking at this barren, desolate lunar plain, appreciating," Cameron said.

Cameron also realized just how isolated he was from any kind of human intervention.

"It's really the sense of isolation, more than anything, realizing how tiny you are down in this big vast black unknown and unexplored place," Cameron said.

"This is the first time in 50 years that humans have returned to the deepest point on the planet," said Terry Garcia, the executive president of mission programs for National Geographic.

The last dive of any kind there was made by a two-man team in a relatively brief expedition back in 1960.

Swiss engineer Jacques Piccard and Don Walsh, a U.S. Navy captain, spent about 20 minutes in the trench during their 1960 dive. However, their view was obscured after their submarine kicked up sand from the sea floor.

"We are on the threshold of what I believe is the greatest age of discovery in the history of the human race. Jim's solo adventure to the deepest point [of the ocean] is an example of that," Garcia said on Monday via satellite on CTV's Canada AM.

Unlike Jules Verne's fictional 19th century explorer Captain Nemo, Cameron's high-tech submarine made the Nautilus look like a bathtub toy by comparison.

It took seven years for scientists and the National Geographic Society to develop the Deepsea Challenger.

Powered by lithium batteries, this 10 tonne sub was designed to withstand the pressures found at the trench's depths which are estimated at 16,000 pounds (7,257 kg) per square inch (6.45 square cm).

The one-seater sub was also outfitted with machinery that Verne himself could not have imagined when he published the sci-fi adventure tale "Twenty Thousand Leagues Under the Sea" in 1870.

According to National Geographic, Cameron collected samples for research in marine biology, microbiology, astrobiology, marine geology and geographics thanks to the breakthrough equipment on the Deepsea Challenger.

The submarine was also equipped with 3D cameras and a tower of LED lights to allow Cameron to film this remarkable journey.

"This lighting system has a capacity to light the equivalent of three American football fields," said Garcia.

Such advancements "are opening up doors that have been closed to us for so many years," said Garcia.

These breakthroughs, coupled with the information gleaned from Cameron's journey, should launch more journeys to the ocean's floor in the near future.

"This is not a one-time event. We will be returning to continue the research and to continue exploring this area," said Garcia.

"This is one of the last blank places on the map. We're just now having the opportunity to fill in that blank space," he said.