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⏵ Course guide · Wyoming ultra

The Drift 100 Course Guide

The Drift 100 is Wyoming’s signature winter ultra, a self-supported run across the snowbound Wind River Mountains near Pinedale that you can take on by foot, fat bike, or ski. It is billed as the highest winter ultramarathon in the country, the temperatures drop below zero, and you are out there for a long, dark night or two with mandatory survival gear on your back or a sled. I will walk you through the course and the format first, then give you pacing and fueling strategy built for the cold and the distance, plus free tools to dial in your own numbers.

⏵ At a glance

The Drift 100 quick facts

Date
Weekend of March 13 to 15, 2026 (100 starts Friday morning)
Location
Upper Green River, Wind River Mountains, near Pinedale, Sublette County, WY
Distances
100 mile (about 103 mi to the finish), 28 mile, and 13 mile
Format
Race it on foot, fat bike, or ski. Self-supported, no drop bags or pacers
Elevation gain
Over 9,000 ft of climbing on the 100; highest winter ultra in the US
100 start
Friday, 9:00 AM, from the Upper Green River parking area
Cutoff
Roughly 48 hr for the 100, all courses close 5:00 PM Sunday, with aid-station cutoffs near miles 25, 50, 67, 83
Qualifier
No Western States, Hardrock, or UTMB qualifier status listed by the race

These facts come from the official race site (course, schedule, and gear pages) and UltraSignup. Snow conditions, the exact date, start times, cutoffs, and the mandatory gear list change year to year, so confirm the current specifics with the race before you register or run.

The course: where The Drift 100 is won and lost

The 100 starts at the Upper Green River parking area and runs about 103 miles of groomed snowmobile trail through the Wind River Mountains, crossing the Continental Divide and finishing up at Kendall Valley. It follows the path of the Green River Drift, an old cattle drive that has moved animals along this same route since the 1890s. Over 9,000 feet of climbing, the highest winter ultra in the country, and four heated aid stations spaced way out near miles 25, 50, 67, and 83. Between them, you are on your own.

The snow is the terrain, and it changes everything

Forget your trail splits. On The Drift the surface is snow, and how it sets up decides your whole day. Firm, fast groomed trail and you can move. Soft, sugary, or churned-up snow and even a flat mile turns into a slog that eats your legs and your time. The grade matters less than the snow does, so go in expecting to move slower than any summer 100 you have run, and do not panic when your pace looks ugly. That is just what running on snow at altitude costs.

Because this is billed as the highest winter ultramarathon in the United States, you are also doing all of this in thin, cold air. That makes the climbs feel harder and your recovery slower, so settle into a patient, sustainable effort early and let the long clock work for you.

The night, the cold, and staying on top of yourself

You will run through at least one full night out here, and in a slow year, two. The temperatures sit below zero on a normal day and have dropped near minus 40 with wind and blowing snow. That is where The Drift gets genuinely dangerous, and it is why the race makes you carry real survival gear. The night is not just dark, it is cold enough to hurt you if your systems fall apart.

The job at night is to stay warm without sweating through your layers, keep your water and food from freezing, and keep your hands and feet working. Manage your insulation like a dial: add a layer before you stop, shed one before you overheat on a climb. Runners get into trouble here when they let themselves get wet from sweat and then chill the moment they slow down.

Self-supported: no drop bags, no pacers, no bailout

This is the part people underestimate. There are no drop bags, no pacers, and no cell service on course, and no outside or motorized assistance is allowed. The four aid stations are manned and heated and you can warm up, melt water, and eat there, but you cannot sleep in them, and everything you need between them rides with you. Most runners on foot tow a small pulk sled to haul the mandatory kit, which also helps on the downhills, while some go with a big pack.

So the race is really a self-sufficiency test. You carry a 0°F sleeping bag, a pad, a tent or bivy, a stove and fuel, water you keep from freezing, lights, goggles, and a tracker, and you manage all of it solo for up to two days. Practice living out of that exact setup before race day, because fumbling your stove or your shelter with cold fingers at mile 70 is how good runners end their race.

Pacing strategy for a cold, snowbound 100

The Drift rewards patience, warmth management, and forward motion way more than speed. With soft snow, altitude, a heavy load, and a roughly 48 hour clock, this is about staying steady and not making a cold-night mistake, not about hitting a pace chart.

Pace by effort, and respect the snow and altitude

Your flat-ground pace is meaningless on snow at altitude with a sled in tow. Run the whole thing by effort, hold an output you could sustain for two days, and power hike the climbs without a second thought. The classic blowup here is pushing the early miles because the trail is firm and you feel strong, then paying for it when the snow softens, the night hits, and the cold starts taxing you. Use a grade-adjusted pace to turn your real fitness into honest effort targets, then ride the long clock instead of racing it.

Build a finish window and back it into the cutoffs

Do not guess your Drift finish off a summer 100 time. Snow, altitude, the gear load, and the stops to manage cold all add real hours, and even the running course records sit around 29 to 31 hours. Build a vert-aware finish prediction, then pad it for winter and work backward into the cutoffs at the aid stations near miles 25, 50, 67, and 83, plus the 5 PM Sunday close. That tells you the real buffer you need at each checkpoint so a slow, cold stretch in the dark does not quietly end your race.

Aid stations are warm-up shelters, so use them with intent

The four heated aid stations are the only warm spots on the whole course, so treat each one as a planned reset, not a hangout. Get in, eat real hot food, top off and thaw your water, dry or swap anything wet, fix your feet, and get back out before you cool down and stiffen up. You cannot sleep in them, and long aimless stops in the warmth are where the clock and your body temperature both turn against you. Know exactly what you need to do at each stop before you arrive.

⏵ Free tools to pace this course

Fueling strategy for the cold and the duration

You are fueling a one-to-two-day effort in deep cold, where your calorie burn is high, your gels freeze, and your appetite hides. On The Drift, eating and drinking are survival tasks, not just performance ones.

Carbs: keep eating, and keep it from freezing

Over a long winter effort, aim for a steady carb intake in the rough 60 to 90 grams per hour range, but the bigger battle is the cold, not the math. Staying warm burns extra calories, and the cold blunts your hunger right when you need to eat the most, so make eating a scheduled habit instead of waiting to feel like it. Gels and bars turn into bricks in sub-zero air, so carry food that still works frozen, keep some next to your body, and lean on warm calories at the aid stations. A runner who stops eating out here gets cold fast, and cold and underfueled is how races end on The Drift.

Fluid and sodium: you still dehydrate in the cold

It is easy to forget to drink when it is freezing, but you are still sweating under your layers and losing water to the dry, cold air, and dehydration creeps up on people in winter races. Mandatory gear includes at least two liters of water you have to keep from freezing, so use an insulated bottle or hose setup, keep it close, and melt and refill at every heated stop. Warm drinks pull double duty: they hydrate you and they raise your core temperature when you are getting cold. Keep sodium going in alongside the fluid so you absorb it instead of just sloshing it around.

⏵ Build your fueling plan

Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and a long Drift effort with the free ultra fueling calculator. Browse the rest of the free running tools at the tools hub.

Train for the conditions

The Drift asks for a strange mix: 100 mile endurance, altitude, a heavy sled or pack, and real winter survival skill. These guides go deep on the parts that decide whether you finish.

⏵ Free calculators for this race

Run your Drift 100 numbers with our free, no-signup tools, then let Summit Line tie them together with your real fitness and a winter hundred this demanding.

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⏵ Train for it with Summit Line

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The Drift 100 FAQ

How hard is The Drift 100?

The Drift 100 is one of the hardest winter ultras in North America, and the difficulty is mostly about the cold and the self-sufficiency, not the climbing. You cover about 103 miles of snow-covered trail across the Wind River Mountains with over 9,000 feet of gain, and the race bills itself as the highest winter ultramarathon in the United States. Temperatures regularly drop below zero and have hit close to minus 40, the course holds a full night or two of darkness, and there are no pacers, no drop bags, and no cell service. You have a roughly 48 hour window, you carry mandatory survival gear the whole way, and you have to keep yourself fed, warm, and moving on your own. It is as much a winter survival problem as a footrace.

How much climbing is in The Drift 100, and how high is it?

The 100 has over 9,000 feet of elevation gain across roughly 103 miles, on groomed snowmobile trail through the Wind River Mountains, and it crosses the Continental Divide. The bigger story is the altitude: The Drift is billed as the highest winter ultramarathon in the United States, so you are working hard in thin, frigid air the whole way. The grade is not the thing that breaks people here. The cold, the soft snow, and the altitude are.

What gear do I need for The Drift 100?

The Drift has a serious mandatory gear list because it is a real winter survival race, and they check it before the start. You carry a sleeping bag rated to at least 0°F (the manufacturer rating), an R-value sleeping pad, and a real tent or bivy (no tarps or space blankets). You also need a stove with fuel, at least two liters of water kept from freezing, a cup or pot and spoon, a windproof insulated layer with a hood or an insulated hat, goggles (sunglasses do not count), red blinking lights and reflective tape, a headlamp with spare batteries, and a Garmin inReach or SPOT tracker. Most runners haul it all in a pack or tow it on a small sled. Confirm the current list on the race gear page before you pack, because it gets updated.

What are the cutoff times for The Drift 100?

The 100 runs on a roughly 48 hour clock, and all courses close at 5:00 PM Sunday. Along the way there are progressive cutoffs at the four manned, heated aid stations, which sit near miles 25, 50, 67, and 83, so you cannot bank all your buffer for the end. The organizers have waived the overall limit in an extreme-weather year before, but you should plan to make every checkpoint with margin. Pull the current cutoff schedule off the official course page and build your plan backward from those times.

How cold does The Drift 100 get, and how do I prepare?

Cold enough to be the whole challenge. Race-day temperatures routinely sit below zero and have dropped close to minus 40 with wind and blowing snow, and you spend at least one full night, sometimes two, out on the snow. The prep that matters most is dialing in your cold-weather systems before race day: a layering plan you can adjust on the move so you never sweat through your insulation, a way to keep water and food from freezing, warm hands and feet, and real practice setting up your shelter and stove with cold fingers. Train in the actual conditions and gear you will race in. The runners who struggle here are usually the ones whose cold-weather kit was a guess.

Can you run The Drift, or do you have to ski or bike it?

You can absolutely run it. The Drift lets every racer pick their mode: run on foot, ride a fat bike, or ski, all on the same snow-covered course. On foot, a lot of finishers tow a small pulk sled to carry the mandatory gear, which also helps on the downhills, while others go with a pack. The running course records are around 29 to 31 hours, which tells you how long even the fast runners are out there. Pick the mode you have actually trained on snow, because soft trail and a heavy load make everything slower than your summer numbers.

This guide is independent and for planning only. The course details, dates, start times, cutoffs, aid stations, and the mandatory gear list come from public sources and can change year to year, and winter snow and weather vary a lot from one edition to the next, so confirm the current specifics with the official race before you register or run. The fueling and pacing advice is general and not medical advice.