A British team is set to make history by becoming the first people to reach Antarctica's Pole of Inaccessibility without mechanical assistance.
The team has been using wind power to speed its progress
The four-man group began their 1,770km (1,100 mile) trek at the beginning of December, using only skis and kites to pull their 120kg sledges.
With favourable weather conditions, the men hope to complete the remaining 320km (200 miles) in the next six days.
The Pole of Inaccessibility marks the centre of Antarctica.
It is the point on the continent that is furthest from any coast.
The members of Team N2i - Henry Cookson, Rory Sweet, Rupert Lonsdon and guide Paul Landry - have been using a combination of skis and kites, ranging in size from 3.5 to 6.5m (11.5-21.5ft), to help them cover the distance.
"We are within spitting distance now, so we are going to try to get in 50-80km each day and do it within four to six days," team member Henry Cookson told BBC News via satellite phone.
"Potentially, we could do it within three days but at this stage we have come so far and put our bodies through so much, the last thing we want to do is injure ourselves."
The team travelled from Cape Town, South Africa, at the end of November before setting out from Novo on 3 December.
The four men have been able to cover about 100km (60 miles) in a day when there has been favourable wind conditions.
But Mr Cookson added that they took nothing for granted: "There is no such thing as a weather forecast out here, we are in such a remote location that there is no data; no-one really knows what goes on out here.
"But from looking at the snow, it is very rough which suggests there is a strong prevailing wind. So we are pretty confident things will be OK."
One of the biggest problems they had to face was coping with wind chills lower than -50C (-58F), he said.
"The longer the days are, and we've had 14 to 16-hour days, the more tired the body becomes and the less able it is to cope with the cold.
"When you tangle your kite and have to take off your gloves to unknot it, it is obviously not comfortable nor ideal."
The Pole of Inaccessibility was first reached by a Russian expedition back in the International Geophysical Year of 1958.
A team of scientists made it to the remote outpost, 3,800m (12,500ft) above sea-level, using tracked snow vehicles to carry out a series of meteorological observations.
Now abandoned, a hut built by the Russians still stands on the site, along with a bust of former USSR President Vladimir Lenin.
The team's portable base, minus a bust of Lenin
Although Team N2i's trek has not involved any research, it has a connection to Russian Antarctic scientific community.
After reaching their goal, the four men will be taken by plane to the Vostok research station 960km (600 miles) away.
They will also leave the continent from another Russian base, Molodezhnaya, on a scientific ice-breaker called Akademik Feodorov, before arriving back in Cape Town in early February.
A member of the team's UK-based support crew said they had been in regular contact with the Guinness Book of Records, and that everyone was confident that the four men would be recognised as the first people to reach the Pole of Inaccessibility without mechanical assistance.
The team hopes its efforts will raise £150,000 for the Somerset-based Calvert Trust, an organisation that enables people with disabilities to participate in a variety of outdoor activities.