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⏵ Course guide · Idaho ultra

Wilson Creek Frozen 50K Course Guide

The Wilson Creek Frozen 50K is a cold, snow-and-mud winter ultra on the Wilson Creek trail system in the Owyhee Mountains south of Nampa, and it kicks off the Idaho Trail Ultra Series every January. It climbs through the Reynolds Creek gorge to the top of Wilson Peak early, then sends you back out for a second loop in whatever the high desert throws at you that day. I will walk you through the course first, then give you a pacing and fueling plan built for the climbing and the cold. There are free calculators along the way to dial in your own numbers.

⏵ At a glance

Wilson Creek Frozen 50K quick facts

Date
Saturday, January 23, 2027 (mid-to-late January)
Location
Wilson Creek trail system, Owyhee Mountains, near Melba, Owyhee County, ID (about 30 min south of Nampa)
Distances
50K (20.3 mi loop + 10.8 mi loop), 20.3 mi, and 10.8 mi
Elevation gain
50K: about 6,000 ft · 20.3 mi loop: about 4,500 ft · 10.8 mi loop: about 1,500 ft
Start
50K & 20.3 mi: 7:30 AM MST (check-in from 6:00 AM) · 10.8 mi: 9:00 AM
Cutoff
50K: must leave Pulse Paradise aid (mile 20.3) by 3:00 PM, about 7.5 hr
Series
First race of the Idaho Trail Ultra Series (no WS, UTMB, or Hardrock qualifier listed)

These facts come from the official race pages and public race reports. Check the current date, start times, cutoffs, and aid stations in the race-day details before you commit. Winter race logistics change year to year, and conditions swing hard.

The course: where Wilson Creek is won and lost

The 50K is a 20.3 mile loop followed by a 10.8 mile loop, run clockwise, for about 6,000 feet of total climbing. It is roughly 43 percent singletrack and 57 percent dirt road and doubletrack, so it is more runnable than the vert number suggests, right up until the snow and ice make it not. The course threads the Reynolds Creek gorge along the historic China Ditch, then climbs to the summit of Wilson Peak.

Wilson Peak: the big climb comes early

Do not let the early miles fool you. The defining feature of this course is a long climb of roughly 2,500 feet up to Wilson Peak inside the first 7 miles or so, topping out around 5,340 feet, which means a big chunk of the whole day’s vert lands before you are even warmed up. That is a trap if you treat it like a race. Hike the steep pitches, keep your effort honest, and get to the top with something left, because you still have most of the 50K and a second loop ahead of you.

In a normal year this climb is just a grind. In a snow year it is a grind through slick, dry snow with poor traction, and the descent off Wilson Peak can mean hurdling knee-deep drifts and picking your line across rocky sections to find shallower footing. The people who do well here are strong and patient on this climb and do not panic about the clock.

The gorge, the China Ditch, and the rolling middle

Between the big climb and the aid stations, the course rolls through the Reynolds Creek gorge along the China Ditch, a historic cut that gives this race a lot of its character. This is classic high-desert mountain trail: rolling singletrack, dirt roads, and semi-rugged sections with wide-open vistas when the sky is clear. It is the runnable part of the day, so if your legs and your footing are good you can make real time here.

The catch is always the surface. Frozen ruts, mud that froze solid overnight, fresh snow on top of old ice. None of it is technical in the rock-garden sense, but all of it slows you down and chews up energy, so plan your pace around the conditions you actually have underfoot, not the splits you would run on dry trail.

The second loop and the 3 PM gate

The 50K sends you back through the start area at the Pulse Paradise aid station around mile 20.3 to begin the shorter 10.8 mile loop, which adds about another 1,500 feet of climbing. This is where the race is decided for a lot of people, because you have to leave Paradise by 3:00 PM to keep going. If you bled too much time on the climb or in the snow on the first loop, that gate ends your day right here.

If you make the cutoff with margin, the second loop is a question of holding it together as the temperature drops and the light starts to go. Have a headlamp if you are heading out in the afternoon, keep eating even when you do not feel like it, and stay on top of staying warm. The last loop rewards runners who kept something in reserve and never let themselves get cold and stiff.

Pacing strategy for a climbing-heavy winter 50K

With about 6,000 feet of gain, an early 2,500-foot climb, and snow or ice that can erase your normal pace, Wilson Creek is about managing effort and the clock, not hitting a flat-ground split. Run the early climb by feel, and respect the 3 PM gate at mile 20.3.

Pace the Wilson Peak climb by grade, not the watch

Your flat-ground pace is meaningless on the climb to Wilson Peak, and it is even more meaningless on snow. What matters is steady, sustainable effort, so hold an output you can keep up the grade and hike the steep stuff without guilt. The classic mistake is hammering the first big climb because the day is fresh and the legs feel good, then having nothing for the second loop. Use a grade-adjusted pace to turn your real fitness into honest climbing and descending targets so you do not torch the first 7 miles.

Build a finish prediction that respects the vert and the cutoff

Do not guess your Wilson Creek finish off a road 50K time. The 6,000 feet of climbing, the slick footing, and the cold all add real minutes, sometimes a lot of them in a snow year. A vert-aware finish prediction that accounts for this course’s climbing gives you a realistic window, and just as important, it lets you work backward into the 3:00 PM gate at mile 20.3 so you know how much buffer you actually have when you roll into Paradise.

⏵ Free tools to pace this course

  • Grade-adjusted pace calculator to turn your flat fitness into honest targets for the Wilson Peak climb and the rolling miles.
  • Race-time calculator for a vert-aware finish prediction on this course’s climbing, so you can plan against the 3 PM cutoff at mile 20.3.
  • Race-equivalent calculator to turn a recent race result into a Wilson Creek goal you can actually hold in winter conditions.

Fueling strategy for the cold and the duration

Most runners are out on the Wilson Creek 50K for a long winter day, and the cold changes the fueling game. Your fluids can freeze, your hands stop working, and it is easy to forget to eat when you are cold, so carbohydrate, fluid, and a plan you can execute with numb fingers all matter as much as fitness.

Carbs: steady, easy to eat, and cold-proof

For a long winter 50K, aim for around 60 to 90 grams of carbohydrate per hour, and only push the higher end if your gut is trained for it. The wrinkle here is the cold: gels turn to glue, bars freeze into bricks, and your appetite quietly disappears when you are chilled. Lean on fuel you can actually get down with gloves on and a numb face, keep it steady instead of gambling on big late doses, and practice your exact race-day carb rate on cold long runs so it is automatic.

Fluid and warmth: do not let your drink freeze

You still sweat and still need fluid in the cold, even though you may not feel thirsty, so keep drinking on a schedule rather than by feel. The real winter problem is freezing: hydration hoses and bottle valves ice up fast at these temps, so insulate them, blow the line back after each sip, or run soft flasks inside a layer. Sodium needs are lower than a hot summer race, but do not zero it out. Most of all, stay ahead of getting cold and stiff, because a runner who lets their core temp drop stops eating, slows down, and unravels.

⏵ Build your fueling plan

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

⏵ Train for it with Summit Line

Get a race-day plan built around YOUR fitness, this exact Wilson Creek course profile, and your projected splits. Summit Line reads your real training, builds a plan for the early Wilson Peak climb, and rehearses your fueling so race day is something you execute, not guess at.

Start free →Explore the demo

Wilson Creek Frozen 50K FAQ

How hard is the Wilson Creek Frozen 50K?

It is a genuinely hard winter mountain 50K, and the conditions are half the difficulty. The 50K stacks about 6,000 feet of climbing across a 20.3 mile loop and a 10.8 mile loop, and it summits Wilson Peak early, so you are climbing hard before you are warmed up. Then there is the weather: January in the Owyhees can hand you anything from 40s and mud to single-digit temps with wind, ice, and knee-deep drifts. The footing slows everyone down, so this is more about staying steady and warm than about running a fast time.

How much climbing is in the Wilson Creek Frozen 50K?

The full 50K has roughly 6,000 feet of total elevation gain. That breaks down into about 4,500 feet on the 20.3 mile loop and about 1,500 feet on the 10.8 mile loop, with the course running from a low around 2,565 feet up to a high around 5,340 feet at Wilson Peak. The single biggest piece is a long climb of roughly 2,500 feet up to Wilson Peak inside the first 7 miles, so a big chunk of the day’s vert comes at you early.

What are the cutoff times for the Wilson Creek Frozen 50K?

The key cutoff for the 50K is that you must leave the Pulse Paradise aid station at mile 20.3 by 3:00 PM, which works out to about 7.5 hours from the 7:30 AM start. That is the gate that ends a lot of 50K days, because it falls right where the second loop begins. If you are leaving Paradise in the afternoon you are told to have a headlamp, since the back half can run into fading winter light. Always confirm the current cutoffs in the race-day details before you start.

Where are the aid stations on the Wilson Creek Frozen 50K?

For the 50K, plan on aid stations at roughly miles 2.5, 13, 20.3 (Pulse Paradise, the start of the second loop), and 25.3, with a later one near mile 27.3 noted some years. The gaps are not huge by ultra standards, but in cold and snow your fluids can freeze and your hands stop working, so you cannot treat aid like a warm road race. Carry what you need to stay fed and moving between stations, and confirm the exact aid layout in the current race-day info.

What is the terrain and weather like at Wilson Creek?

The 50K is a mix of about 43 percent singletrack and 57 percent dirt road and doubletrack, routed through the Reynolds Creek gorge along the historic China Ditch before climbing to the summit of Wilson Peak. The footing is high-desert mountain trail that, in January, is usually some combination of frozen ground, fresh snow, slick dry snow, ice, and mud. Conditions swing wildly year to year, from temps in the 40s to sub-zero with wind, and past years have started in the single digits with knee-deep drifts up high. The race advises traction devices and/or poles, a whistle, a space blanket, and a headlamp for the longer distances.

Is the Wilson Creek Frozen 50K a good first 50K?

It can be a great first ultra if you respect the winter side of it, but it is not a soft introduction. The early Wilson Peak climb, the snow and ice underfoot, and the cold all ask for specific prep, and the 3:00 PM cutoff at mile 20.3 is real. If you train climbing on tired legs, practice moving in the cold with the gear you will actually carry, and rehearse eating when your hands are numb, most prepared runners can finish. If you have never run in snow or managed cold-weather fueling, build that in well before race day.

This guide is independent and for planning only. The course details, dates, start times, cutoffs, and aid stations come from public sources and can change year to year, and winter conditions vary wildly, 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.