Yukon Arctic Ultra, which calls itself the world's 'coldest and toughest,' kicks off in Whitehorse

How about racing in Arctic temperatures, razor-sharp winds and endless dark nights?

For some athletes, these conditions call for the perfect challenge. About 35 competitors left Shipyards Park in Whitehorse on Saturday morning for the 19th edition of Yukon Arctic Ultra.

Racers who do the Ultra — which is taking place from Feb. 4 to Feb. 17 — can either run, cross-country ski or bike. They also choose the race length between 26-mile marathon (42 kilometres), 100 miles (160 kilometres), 300 miles (483 kilometres) or the full 430 miles (692 kilometres), which is the distance from Whitehorse to Dawson City.

Meet some of the Yukon Ultra Racers:

Robert Pollhammer, the ageless organizer of the event, says the race is unique in many ways.

"It's a tough one, for sure," he told CBC News on Saturday. "We have ... very different kinds of people. Old, young, very fit and people sometimes who think they could never do this. But they surely do. All very motivated!"

For Arnie Owsley, the desire to compete again has been burning quietly for more than 20 years. The 53-year-old man from Utah, United States, was one of the first participants in the inaugural race in 2003.

Owsley, however, hadn't found the space to return until now.

"I didn't lose any feet, I actually finished it," he said Saturday, as he explained the lengthy pause.

"It's just the competitive spirit said to me, 'Hey go back and see if you can do it, maybe beat your time. If not, meet a lot of great people and enjoy the race.'"

Owsley says he believes he's in better shape than the 33-year-old man he was when he first competed in the Ultra.

"Older, wiser ... as the saying goes," he said. "I'll try just to move at a steady pace and keep moving."

'A perfect year'

The Arctic Ultra attracts athletes from all over the world. Among them is first timer Jack Chiang, from Taiwan, who is competing in the 26-mile marathon. Chiang, 41, says he was inspired by his friend, the Taiwanese ultra-marathon runner Tommy Chen, who's returned to the Ultra for a second time after competing 10 years ago.

"He's a hero in Taiwan," Chiang said of Chen on Saturday. "It's exciting [to run with him] ... This is a very big challenge, because of the weather. Too cold for me!"

Chiang says he traveled to Japan in order to prepare for the Yukon's climate and snowpack, but this will be the longest run for the athlete so far.

"I'm bringing heavy jackets, hot water, some food," he said. "Chocolate and energy bars."

While racers may be worried about whatever sub-zero temperatures the territory throws at them, Pollhammer says he's not worried about the weather this year.

"Looks like it could be a perfect year for us," Pollhammer said. "We wanted it cold, it's like -15 Cright now. Perfect. It doesn't go to -40 C and that's what we want."

He emphasises the need for athletes to self-monitor, eat and sleep enough.

"And don't sweat through the layers," he said.

According to the event's guideline, all checkpoints will have hot water, tea and coffee. Participants will be able to re-supply for food in Carmacks and Pelly Crossing. For orientation, the trails are marked with Yukon Quest markers, including wooden sticks with a fluorescent top.

They can also expect to see staff patrolling on snowmobile at least once every 24 hours.