Antarctic explorers finally find the ill-fated HMS Endurance almost 2 miles below the ocean in 'the world's most challenging shipwreck search'

• The wreck of Sir Ernest Shackleton's legendary Endurance ship was discovered this month.
• An expedition used coordinates from 1915 and advanced subsea technology to locate it.

The wreck of the HMS Endurance ship, which famously sank after being trapped in pack ice in Antarctica's Weddell Sea in 1915, was discovered by an expedition this month.

Led by the renowned British explorer Sir Ernest Shackleton on his Antarctic expedition, the Endurance had been missing for more than a century.

Many presumed that it would have been destroyed or seriously degraded after 107 years on the seafloor.

But when the Endurance22 expedition of explorers found it in March this year, it was surprisingly "intact" and in remarkable condition.

"This is by far the finest wooden shipwreck I have ever seen," said Endurance22's director of exploration Mensun Bound. "It is upright, well proud of the seabed, intact, and in a brilliant state of preservation."

Even the name "Endurance" is well preserved and visible across the stern.

The Endurance was frozen in time because the sea life that would typically feed on wood was unable to survive in the icy waters of the Antarctic, deep-sea polar biologist Michelle Taylor told BBC News.

However, other marine life has colonized the ship over the past 100 years.

"The Endurance, looking like a ghost ship, is sprinkled with an impressive diversity of deep-sea marine life — stalked sea squirts, anemones, sponges of various forms, brittlestars, and crinoids, all filter feeding nutrition from the cool deep waters of the Weddell Sea," Taylor said, per the BBC.

The Endurance22 expedition located the lost ship at a depth of 9,869 feet, almost two miles down. It was approximately four miles south of the position originally recorded by the ship's captain Frank Worsley a century ago.

Worsley's "navigational skills" and "detailed records" from November 1915 were "invaluable" in helping to locate the shipwreck, Bound said.

The expedition used the historic coordinates alongside advanced technology to scan a 150-square mile zone for signs of the missing vessel, according to The New York Times.

Technicians ran undersea drones in that zone for two weeks, day and night, to scan the seafloor with sonar for the Endurance, The Times reported.

The drones carried radar equipment on either side, which were able to scan vast sections of the seafloor beneath it, the paper said.

'The world's most challenging shipwreck search'

For weeks, the expedition had no luck. John Shears, the expedition leader, described the mammoth task of locating a ship in remote and icy waters as "the world's most challenging shipwreck search."

However, on the afternoon of March 5, the drone sent back sonar images suggesting the Endurance had finally been discovered, days before the license to explore the area expired, per The Times.

Four days later, the discovery was made public. Shears described that moment as "polar history."

The ship will not be touched while being surveyed and filmed, Endurance22 said and is now protected as a Historic Site and Monument under the Antarctic Treaty.

"However, it is not all about the past," said Bound. "We are bringing the story of Shackleton and Endurance to new audiences and to the next generation."

A tale of survival and endurance

Shackleton's Imperial Trans-Antarctic Expedition is one of the best-known tales of survival and endurance.

The expedition set out in 1914 to make the first land crossing of Antarctica but had to abandon the mission when the Endurance became trapped in pack ice in January 1915.

The crew had to abandon the ship and set up a makeshift camp on the ice. Shackleton hoped that the ice would break when spring arrived, allowing the ship to drift towards safety, but instead, water seeped in and eventually sunk the Endurance.

Shackleton and his crew camped on ice floes for months before rowing hundreds of miles to Elephant Island in open lifeboats.

Shackleton, Worsley, and four other crew members then braved another epic journey to South Georgia whaling stations on the open boat James Caird. Some of the men then crossed the island, across dangerous mountains and glaciers, to reach Norwegian whales.

Rescue missions began on August 1916, and all of the 22 members of the crew on Elephant Island were saved.

Shackleton returned to South Georgia in 1921 for another expedition. He died there of a heart attack at 47-years-old and is buried on the island.

Stefanie Arndt, a sea ice physicist who was on the expedition, said on Twitter that the Endurance22 team visited Shackleton's grave after discovering the ship.

"An emotional end to a long story," she wrote.