A 66-year-old Londoner has completed a 700-mile sled journey along the border of Canada and Alaska last completed by polar explorer Roald Amundsen in 1905.
Tim Oakley was the leader of a four-man, 22-dog team that reached the town of Eagle on Monday.
The group endured temperatures of -50C on the 29-day trip.
Mr Oakley told the BBC he lost about 25lb (11kg) and suffered mild frostbite, but felt he still had another big expedition in him.
The team - which was supported by the Royal Geographical Society - set off from Herschel Island on 28 February.
Unlike Amundsen, it had GPS systems, satellite phones and food drops from the air.
But the Norwegian explorer followed a trading route with trails and guesthouses - most of which are now gone.
As Mr Oakley's team set off in -30C temperatures, with an additional -15C windchill, they hit "pretty nasty" running water on a channel between Herschel Island and the mainland.
"This freezes onto the rails of the sled and onto the dogs' legs, so each time we run through it we have to stop, hack the ice off the sled with an axe [and] try to get the dogs as free from the ice as possible," explained Mr Oakley on his blog.
He said that by 1 March they were "cold, wet and very miserable", with no fire.
On 4 March the team reached a ranger's hut, where they were able to light portable stoves and dry out wet gear.
"The boots took a whole night to unfreeze," Mr Oakley said.
Three days later, after crossing a vast frozen lake that "creaked and groaned" as they went over it, they crossed the border into Alaska.
The going was easier as they headed southwards despite a snowstorm that left them huddled in tents for a day.
By last week the weather was warmer and the dogs had to stop periodically because the -7C temperatures left them overheated.
The team made it to Eagle (population 86) with "only mild frostbite on various fingers and toes" and the dogs in good condition.
"What amazing dogs these have been!" said Mr Oakley. "What a feat of endurance to have pulled a heavy sledge 700 miles in bitter temperatures over extreme terrain and still be wagging their tails every morning."
Born in Norway in 1872, Amundsen was the first explorer to reach the South Pole and to circumnavigate the Arctic. He was also the first person to sail through the Northwest Passage - sledging south from Herschel to Eagle where he sent a telegram announcing the feat.
In the 1920s he began making trips towards the North Pole with varying success. He flew across the Arctic in 1925 and again later in an airship.
Amundsen disappeared in 1928 after he flew to the rescue of a ship lost in the Arctic.
Mr Oakley said he was looking forward to enjoying a "glass of wine and a decent meal" with his family in Fulham.
He added: "I'm not going to give up yet. I'll be 67 this year and I reckon I've got a few more in me yet. Another big one."