WELLINGTON, New Zealand -- Six Americans have just ended a second year of what looks like an impossible mission -- carving out a road to the South Pole.
The 1,020-mile "ice highway" from the coast directly south of New Zealand will enable hundreds of tons of supplies and equipment to be hauled across the world's most inhospitable wilderness on tractor-pulled sleds to the pole's Amundsen-Scott Base, a U.S. research station.
Currently, cargo planes fly in scientists and supplies during the four-month summer.
Where once there was only ice wilderness, now there is a packed surface 20 feet wide and lined with green flags, winding through huge crevasse fields, snow "swamps" and flat pack ice.
After two summers of hard going, the $20 million South Pole Traverse Project has covered 425 miles, and manager John Wright is convinced it can be completed, though not by next summer as originally hoped.
The completion date is the end of the polar summer in 2006, followed by an international environmental review before it can be used, probably no more than three times a year.
In contrast, C-130 cargo planes use ice runways in Antarctica several times a day during the summer.
"It is just a matter of time and work," Wright told The Associated Press in an e-mail interview from the U.S.-run McMurdo base on the Antarctic coast.
"Last year it took us three months to go three miles across a crevasse field ... full of dangerous hidden crevasses. This year we were ... 'breaking trail,' a long, slow slog in soft snow."
In the "snow swamp," a 180-mile-wide, 6-foot-deep field of powder snow, progress slowed to as little as 10 miles a day for the three tractors towing accommodation huts and fuel tanks.
Instead of gliding along the surface, tractors and sleds plowed deep into the snow, stuck fast and had to be hauled out by vehicles traveling behind them.
Wright said the route's newly compacted surface will remain solid over the winter and be useable next year, though the road itself will move, as the whole ice shelf is in slow, fluid motion.
From one summer to the next the crevasse field moved about 1,000 feet north and grew about 100 feet longer.
"The ice had stretched," he said.
Also, five new crevasses appeared in the road surface during the eight-month winter and had to be filled with snow and ice before the tractors could continue. Crevasse filling is expected to be an annual chore.
The U.S. National Science Foundation is paying for the project.
Wright said early studies by U.S. Army cold regions researchers estimated the road eventually will mean a 30-day round trip between coast and pole.
When work stopped in late January, the team was still 270 miles from a vast area known as the Polar Plateau, and a long, flattish run to the South Pole, Wright said.
Alan Hemmings, an Australian environmentalist, said the road "is the greatest single footprint of activity we've seen in the Antarctic" and has "the potential for far-reaching impacts."
Apart from the 13,000 tourists who visited Antarctica by sea last year, Antarctica's scientific community has to cope with ever more adventurous visitors.
In December they signaled their frustration by refusing to refuel the homemade plane of a stranded Australian aviator, accusing him of failing to prepare properly for his polar flight. He finally got fuel from another aviator whose expedition was aborted by bad weather.
Hemmings said tour operators "might want to piggyback on this U.S. route -- and the U.S. will be able to do little about that."
Hemmings is senior adviser to the Australian-based Antarctic and Southern Oceans Coalition, an environmental advocacy group.
Commercial operators already take tourists across the frozen landmass to the South Pole by plane. The more robust adventure tourist can get about on skis.
"The route may attract other activity ... facilitate greater access," Hemmings said. "We are beginning to change Antarctica."
Karl Erb, head of the National Science Foundation's Antarctic program, said the route is subject to stringent international safeguards. Its "sole goal is to provide an alternative to air-ferrying cargo and scientific personnel to the pole," he said.
The first person to drive to the South Pole was Sir Edmund Hillary, the Everest conqueror from New Zealand, using a modified farm tractor fitted with tracks. He arrived Jan. 4, 1958, as part of the British Commonwealth Transantarctic Expedition.
It took him 81 days, and only 23 gallons of fuel remained in his tanks when his small team reached the pole.
To Wright, of Silverton Colorado, Hillary is a hero.
"My hat's off to him," he said.