By Sean Smith
Entering Sir Ernest Shackleton's hut on the edge of the Antarctic is like travelling back in time 100 years and becoming part of the expedition that so nearly became the first to reach the South Pole.
Iron pots stand on the wood stove, and bottles of medicine and cans of preserved food can be seen on the wooden shelves.
The men of the Shackleton Centenary Expedition find it particularly moving as they are each descended from members of the original team.
For Henry Adams, a shipping lawyer from Suffolk, it is a chance to try to find the socks that belonged to his great-grandfather, Jameson Boyd Adams, who was Shackleton's number two.
The three-man expedition also includes Henry Worsley, descended from Shackleton's captain (Frank Worsley) and Will Gow, a descendant of Shackleton's brother-in-law (Herbert Dorman).
Shackleton's men were forced to spend an entire winter in the hut before setting out for the Pole as they could only reach this base camp at the end of the Antarctic summer.
But the modern team have arrived in November and are ready to set off straight away.
After spending just a few hours to pay homage to their ancestors and marvel at the survival of the items in the hut, as well as pondering how tough it would have been to travel in Antarctica wearing wool and cotton clothes and sleeping in reindeer skin bags which froze solid after weeks of use, the team begin its own trek.
The three men each have a specialised sled, known as a pulk, for pulling along the ice. It is filled with food, clothing and equipment, and weighs a total of 130kg.
Skiing across the ice, the loaded pulks slide reluctantly behind the men, with a swishing and a crunching across the frozen terrain.
I follow for a while, filming as I go, then reluctantly I have to leave them.
The team is retracing Shackleton's 1908 expedition
Over the past few weeks, we have been getting daily updates on their progress sent via satellite phone, and the details are being posted on the expedition website.
The first leg of the journey south has taken them across the Ross ice shelf. This is a 600-mile long plate of ice that reaches a thickness of 3,000 feet; all of it floating on the waters of the Southern Ocean.
They have had firm snow underfoot, which has enabled them to make good progress, averaging around 10 nautical miles (20km) a day.
After two weeks, half way across the shelf, they were hit by storm force winds and white-out (blowing snow and high winds that reduce visibility to less than a metre and make travel impossible).
But after two days confined to the tents, they were able to set off again and have already passed the first major obstacle, known as "the barrier", a steep slope of ice that marks the edge of the Ross ice shelf.
This has been safely negotiated, as have the crevasses of what is known as the "shear zone", where the Ross ice shelf grinds against the much smaller McMurdo ice shelf.
They must also climb the Beardmore Glacier. Here the gradient will change from flat to uphill and pulling their sleds will be correspondingly harder.
It was here, back in 1908, that Shackleton struggled with deep snow and hidden crevasses.
The Manchurian ponies he had brought to haul the sleds were constantly sinking in to the deep snow and one-by-one they were shot and eaten as the expedition made its gruelling way southwards.
The team will haul all their equipment to the Pole
The Beardmore glacier was named after Shackleton's most prolific benefactor and as they traversed the Trans-Antarctic mountains, they had gone further south than anyone before them.
By this time, all the ponies were dead and the heavy sled - loaded with a cumbersome canvas tent and the meagre rations of pemmican and biscuits - was being dragged by the men themselves.
As they forced their way onwards, the men were constantly falling in to crevasses. On many occasions they were only saved by the ropes that harnessed them to the sled, before being unceremoniously hauled to the surface.
Today, crevasse rescue is a little more sophisticated, but for the three men of the Shackleton Centenary Expedition, the Beardmore glacier will still be a formidable obstacle.
Having to pull their sleds uphill, they will be roped together, which also makes progress awkward
They will be also facing the constant threat of falling through a snow bridge into hidden crevasses large enough to swallow St Paul's Cathedral.
Beyond the Beardmore, they will be on the polar plateau, facing temperatures of -40C and head-winds of 50 mph (80km) or more.
In these conditions, leaving the skin bare for more than a few minutes can lead to permanent injury through frostbite.
On top of that they will have to drag their sleds over iron-hard wind-blown waves and ridges in the snow. Known as Sastrugi, these can turn man-hauling a heavy load in to a nightmare.
Through it all, the members of the expedition will be filming themselves with small cameras.
At 97 miles (156km) from the Pole, they will be joined by another group of descendants for the final section of the trek, and I plan to walk with them on the last stretch to the Pole.
It was this final leg in the harshest of environments that defeated Shackleton a century ago.
The team will have to avoid dangerous crevasses
Dressed in threadbare clothing and constantly battling frostbite, his men trekked southwards but on 9 January 1909 Shackleton realised the game was up.
With his three companions, he made one final march and planted the Union Jack at 88 degrees 23 minutes south, just 97 miles (156km) from the South Pole.
Then with the wind behind them, they turned for home.
The return journey became a race for survival, but all four men lived through the ordeal.
Shackleton was knighted on his return to England and was reputed to have explained his decision to turn back by saying he knew his wife would prefer a "live donkey to a dead lion for a husband".
Despite a later attempt in 1914, Sir Ernest Shackleton never did reach the South Pole.
But hopefully in January 2009, these descendants of the heroic age of polar exploration will finish the journey in his memory, and Shackleton's compass will at last make it to the South Pole.
There are daily reports on the expedition's progress at the expedition website
The expedition is also being filmed for a BBC Two Timewatch documentary in spring 2009