Engineers have completed the first phase of a project to explore an ancient subglacial lake buried 1.8 miles beneath the ice in Antarctica.
The team used a 'tractor train' to tow nearly 70 tonnes of equipment 155 miles through the Ellsworth mountain range to the Lake Ellsworth drilling site.
Scientists will return in November to collect water and sediment from the buried lake using space industry standard 'clean technology'.
They hope the samples will provide clues about the earth's past climate. It could also help scientists assess the present-day stability of the West Antarctic Ice Sheet and implications for future sea-level rise.
The Lake Ellsworth Programme Principal Investigator, Professor Martin Siegert from the University of Edinburgh, said: "The completion of this stage of the mission is a welcome one - we are now one step closer to finding out if new and unique forms of microbial life could have evolved in this environment. The samples we hope to capture from Lake Ellsworth will be hugely valuable to the scientific community. Extracted sediment samples could give us an important insight in to the ancient history of the West Antarctic Ice Sheet, including past collapse, which would have implications for future sea level rise."
The advance party, comprising four British engineers, braved temperatures of minus 35 degrees centigrade as they transported the drilling equipment to the site.
On the final stage of the journey powerful tractors were used to tow heavy containers of equipment on sledges and skis, forming a 'tractor-train' which travelled across deep snow and through steep mountain passes.
Scientists have been planning the investigation for more than 15 years.
During phase two of the project researchers will use a high-pressure drill to create a borehole through 3km of ice. They will then lower a titanium probe to measure and sample the water, followed by a corer to extract sediment from the lake. It will take around three days to drill through the ice and the scientists will have about 24 hours to gather samples before the hole starts to freeze over.
The Lake Ellsworth programme is a consortium, funded by the Natural Environment Research Council (NERC), between British Antarctic Survey and the National Oceanography Centre - and the UK university sector.