Imagine traversing 135 miles of the frozen hinterlands of the North Woods on foot in the dead of winter.

You’ll start in International Falls, Minn., aka the “Icebox of the Nation” and “Frosbite Falls,” and follow the Arrowhead State Trail used primarily by snowmobilers. You’ll drag all your gear and fuel behind you in a sled, sleep outside, and have no support crew but for three checkpoints along the way. And you must finish in Tower in under 60 hours.

You’re part of the Arrowhead 135, which begins Jan. 29, known as one of the world’s toughest, most-extreme ultradistance races.

Now double all that.

That’s what two Twin Cities women, Kate Coward and Kari Gibbons, are attempting this week and next.

Starting Thursday, they began running the 135-mile race route in reverse. (Track them here.) They plan to arrive in International Falls at the start line of the Arrowhead ultra Sunday night. The race begins early Monday, when the two hope to turn it all around and set out with 150 others for the finish line in Tower. If they succeed, they will be the third and fourth people to ever do so and the first women. Last year, there were 156 racers at the start in 15-degree weather. Seventy-six cyclists, 40 runners and seven skiers made the cutoff. (Coward raced by bike; Gibbons on foot.)

The women, both 38, are city-bound professionals with a curious hobby. Coward, a finance executive at Polaris, grew up in Orono and was a Division I national champion on a crew team at Brown University. After college she got the marathon bug. She has run races all over the world, from Boston to Melbourne, Australia, to Tanzania and Antarctica. Eventually, came Ironman races and then, in 2016, her first winter ultra race at the Arrowhead 135. Competitors either ski, bike or run. Coward rolled by fatbike her first time. Since then she’s done countless other winter ultra races by bike.

Gibbons, who works at Gear West, got into marathon running in her 30s. She didn’t truly hit her stride until she discovered trail races a couple of years later. About her first 10-kilometer trail race she said: “I thought I was going to die, it was so hard. I was totally addicted.”

One week later she signed up for a 50-mile race and the next year she did her first 100-mile footrace. In 2015, she took a crack at winter ultras, including the Tuscobia 80-mile event and the Arrowhead 135.

Gibbons said her experience at Tuscobia, the eponymous ultra event on a state trail in northwestern Wisconsin, was “totally life-altering.”

“It was the hardest thing I had ever done,” she said. “I had no idea what I was doing. My water froze and I went seven hours without eating or drinking anything. My headlight went out. It was many degrees below zero. I was hallucinating. I thought I was going to evaporate at any moment. And then I managed to finish it.”

It is that spirit of self-reliance and survival that drew Coward to these types of events, too.

“The place you get to in your physical body and in your mind can only be experienced when putting yourself in that position — out on the trail in a remote place where you’re cold and tired,” she said. “Everyone has their dark moments. It doesn’t mean you’re weak, you just have to push through that darkness.”

A new plan

Having become fast friends through the ultra-endurance scene this summer, they came up with a new way to challenge themselves: the Arrowhead double.

They’ve done considerable cardio and strength work in preparation. They’ve also employed somewhat unusual training tactics, such as sleeping outside in negative temperatures and meeting in the middle of the night to hike the Luce Line Trail, dragging car tires behind them.

The logistics of their journey are somewhat daunting. They will both drag sleds, or pulks, loaded with gear affixed with special harnesses. The sleds will hold several gallons of water, diluted Coke, bullion cubes and ramen, fruit and nut bars, tortillas with peanut butter and Nutella, dried bananas, and gummy bears among other fuel. They plan to consume 300 calories per hour.

They also will schlep sleeping bags and pads, bivy sacks, a tarp, batteries for safety lights, extra socks, and a first aid kit. The main goal when it comes to gear is to stay dry, which is a major challenge if the temperatures end up warmer than normal. Hypothermia can set in quickly if base layers get soaked with sweat. Trench foot is a concern if the trails are wet and sloppy. This necessitates a steady, methodical approach in an environment that begs one to push through and get it over with.

The pair will sleep outside in sleeping bags and waterproof bivy sacks most of the five nights they are on trail, but will have the chance to get a night or two in a warm bed along the way. On the second night, Gibbon’s boyfriend will meet them with a resupply. They will have three checkpoints during the actual race.

Both women were unable to finish Tuscobia’s 160-mile race on foot at the end of December. They dealt with the extremes of subzero cold and sleep deprivation. They know there are no guarantees in their 270-mile attempt.

They might catch a break with the weather. It’s projected to be relatively warm (daytime teens, some single-digit nights) for a historically cold time of year in the region.

Still, getting the chance to focus on such a singular task — survival — can feel cathartic when compared to the hectic nature of everyday life.

“I’ve been on the Arrowhead Trail in the middle of the night and had an owl swoop into my headlight, and that moment just carried me for hours,” said Gibbons. “It’s about patience and putting one foot in front of the other. Eat-climb-ride the sled down the hill. Repeat. It can be very spiritual.”

What’s more, they say that the trail has much to teach them and they can’t help going back for more.

“You realize out there that our bodies are designed to withstand a lot,” Coward said. “We have a huge capacity to endure so much.”

Mackenzie Lobby Havey is a freelance writer from Minneapolis.