Nervous exhales condensed into frost over the athletes as they prepared to run, bike and ski into the wilderness.

Unlike the start line of the Yukon Quest the day before, the mood at the start line for the Yukon Arctic Ultra Sunday was decidedly subdued.

The temperature was sitting at -36 with the wind chill, and after posing for a group photo, racers in the marathon, 100-mile, 300-mile and 430-mile routes were anxious to get moving. They shared a foreboding knowledge they were heading out to dangerous territory. Forbiddingly cold, with frostbite imminent, they had been told at race briefings the day previous that wrong decisions can alter their race, their safety, even their life.

Race organizer Robert Pollhammer counted down from 10, and thus began a steady procession of feet, ski poles, thick mountain bike tires, and pulks.

This year for the first time, two women from Whitehorse have signed up for the long haul, the 430-kilometre hike to Dawson City. Shelley Gellatly, 50, is a race veteran and the official Yukon liaison who has run the 100-mile and 300-mile routes before. After scratching from the 430-mile in 2013, she is trying again.

“This will be my last kick at the can, for sure,” she said in an earlier interview. Gellatly said she is prepared for the challenges, and even though she is a trail veteran, she was still feeling “scared shitless” in the days before racing.

Jessie Thomson-Gladish, 29, is the other female entrant from Whitehorse. She is a rookie to the YAU, but a seasoned outdoorswoman. She said she was looking forward to the “adventure and the solitude” the trail was sure to bring.

“I’m not scared,” she said. “I’m worried about what I should be worried about: the extreme cold, managing my body temperature right away.”

Her stepmom and her father, Mike Gladish, were visibly apprehensive for her as they wished her well, cheering with a homemade sign. Covered in frost after standing alongside the chute for a short time, the couple said the extreme cold and the pressures of racing left them worried.

“She’s tough and she’s smart,” said Gladish. “But I’ve seen too many people stop thinking in a race atmosphere. There are so many unknowns.”

The YAU is commonly referred to as the coldest, toughest ultra-marathon in the world.

This year’s temperatures are setting the race to live up to its reputation, giving entrants exactly what they bargained for.

The majority of participants in the ultra-marathon length runs are from Europe, where adventure racing and Yukon is a combination that appeals to a niche group of athletes. Many return, year after year, to make attempts at longer and longer routes. Pollhammer, of Germany, explained the appeal lies somewhere between tourism, adventure and the chance to sign their name as one of the few athletes who has completed the internationally renowned race.

While most of the long distance racers are international, 12 of the 16 marathon participants are from Whitehorse. Yesterday, they made the trek up the Yukon River to the Takhini River bridge and onto the finish line at Rivendell Farm.

Virginia Sarrazin, 37 of Whitehorse, came in first, three hours and 47 minutes after leaving the start line.

When second-place finisher Kristin Daniel, 32 of Whitehorse, crossed the finish line and received her finishing medal, she was covered in tiny frost snowballs. She lifted her arms in victory before retreating indoor for a warm drink.

Whitehorse’s Keith Maguire, 39, crossed the finish line in eighth place, and promptly collapsed into his son’s arms for a hug. His daughter Mia, 7, was given a finishers’ medal to slide over her dad’s head before he joined his wife and older daughter on a quick trip to their car to warm up.

Seven racers had scratched upon arrival at Rivendell Farm by Sunday night, but no one had yet hit the help button on their SPOT-GPS devices. In temperatures this cold and during nighttime, pressing the help button means a rescue might be hours or even a day away, and racers are required to survive on their own until then.

As day turned to night Sunday, more marathoners finished their run in Rivendell while the longer-distance runners stopped to adjust gear, fill up on warm water, rest shortly and carry on to their next checkpoint, Dog Grave Lake.

The 100-mile racers will finish today and tomorrow at Braeburn Lodge. The 300-mile participants will press on to their finish at Pelly Crossing. The 31 athletes signed up to race to Dawson, including Whitehorse front-runner Derek Crowe on a mountain bike, have 13 days in which to arrive.

The athletes are not racing for a purse at the end, but will receive a medal for finishing in their category.

The reward, racers have said, is found on the trail.

“It is the trail that drives me out there,” said Gellatly. “There’s something pretty special that happens when travelling on that trail.”