⏵ Course guide · High desert Colorado trail race
Sage Burner Trail Race sends its 50K, 28K, and 15K fields out across Hartman Rocks Recreation Area near Gunnison, Colorado, over technical slickrock, smooth singletrack, and doubletrack, with rolling hills and punchy climbs that make this deceptively tough course a real test of grit. I will walk you through the terrain and fuel stations first, then give you a pacing and fueling plan built for a high desert day, plus free calculators to dial in your own numbers.
These facts come from the official One Love Endurance Events race page and the 2026 race guide. Cutoffs are marked TBA in that guide, so confirm the current specifics before you commit. Race logistics change year to year.
Hartman Rocks Recreation Area sits in the Rocky Mountains about two hours east of Grand Junction and three hours west of Denver, and the race is true to its name: the hills here are covered in sagebrush, with 360 degree views of the Maroon Bells, San Juan Mountains, and the Gunnison Basin.
The course mixes three distinct surfaces: technical slickrock that demands real footwork, smooth singletrack, and doubletrack sections built for speed. That variety is part of what makes this course deceptively tough. It looks rolling and runnable on paper, but the rolling hills and punchy climbs, paired with the high desert climate, wear on you in a way a flat elevation chart does not capture.
The 50K passes seven numbered fuel stations across 30.8 miles, spaced roughly every 3.5 to 4.5 miles apart, which gives you frequent chances to reset rather than carrying huge reserves. Stations stock water, GU Roctane energy and hydration drink mix, soda, peanut butter, bread, chips, bananas, oranges, Oreos, GU gels, pickles, and warm foods like mashed potatoes, ramen, and quesadillas at select stops. This is a cupless race under the Hydrapak Sustainable Racing Program, so bring your own reusable cup, bottle, or bladder to fill at every station.
The race guide itself warns that temperatures start cool in the morning but climb later in the day, and falling behind on nutrition has left many runners struggling to finish, especially on the 50K. Eat and drink early and often rather than waiting until you feel behind, because by the time you notice, the high desert heat has already made up the deficit.
The 2026 race guide lists 50K checkpoint cutoffs of Noon at mile 15.3, 2:00 PM at mile 22.8, and a 4:15 PM finish cutoff at mile 30.8, off an 8:00 AM start. That is roughly 8 hours 15 minutes total, with the back half of the course given noticeably more time than the front.
The slickrock sections are where technical skill matters most, and they are also where a cautious pace costs you the least time relative to how much they can cost you in a fall or a rolled ankle. A grade-adjusted pace target helps you set an honest effort for the punchy climbs, so you are not comparing your splits here to a flat road pace that has no bearing on this terrain.
Because the race guide publishes specific mile-and-time cutoffs rather than a single overall limit, you have real checkpoints to gut-check your pace against as you go. Use a vert-aware finish prediction from your training to see whether your fitness supports comfortably clearing mile 15.3 by Noon and mile 22.8 by 2:00 PM, and adjust your effort early rather than discovering a problem at the final cutoff.
⏵ Free tools to pace this course
An 8 AM start means cool early miles that warm up fast under a high desert sun. The race guide is direct about it: falling behind on nutrition has left many runners struggling to finish, especially on the 50K.
Aim for roughly 60 to 90 grams of carbohydrate per hour. With seven fuel stations across the 50K spaced every 3.5 to 4.5 miles, you have frequent access, so use it to stay consistent rather than skipping stops early and trying to catch up later.
Sodium in the 300 to 700 mg per liter range covers most runners here. Lean toward the lower end for the cool early miles and push higher as the high desert sun takes over through the middle and late stations, especially on the exposed slickrock and doubletrack sections.
⏵ Build your fueling plan
Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and a warming Gunnison high desert 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 slickrock and rolling-climb course profile, and your projected checkpoint splits. Summit Line reads your real training, builds a plan for technical high desert terrain, and rehearses your fueling so race day is something you execute, not guess at.
Do not let the "small race" feel fool you. The 50K covers 30.8 miles at Hartman Rocks Recreation Area, mixing technical slickrock with smooth singletrack and doubletrack, and the rolling hills and punchy climbs add up over a high desert day that can run cool at the 8 AM start and hot by afternoon. It is a genuine test of grit, and the race guide itself does not shy away from calling the course deceptively tough underneath its rolling profile.
For the 50K, the 2026 race guide lists checkpoint cutoffs of Noon at mile 15.3, 2:00 PM at mile 22.8, and a finish cutoff of 4:15 PM at mile 30.8, off the 8:00 AM start. That works out to roughly 8 hours 15 minutes total. The guide marks these times as TBA, so confirm the current cutoffs before race day, but plan around that rough 8-hour-plus window either way.
Aim for roughly 60 to 90 grams of carbohydrate per hour, and keep sodium in the 300 to 700 mg per liter range, especially since the race guide itself flags that mornings start cool at Hartman Rocks but temperatures climb through a high desert afternoon. The 50K has 7 fuel stations spaced every 3.5 to 4.5 miles with water, GU Roctane drink mix and gels, soda, peanut butter, bread, chips, bananas, oranges, and warm foods at select stations. Note this is a cupless, BYOC race under the Hydrapak Sustainable Racing Program, so bring your own cup, bottle, or bladder to every stop. Build your numbers with the free ultra fueling calculator before race day.
Hartman Rocks mixes technical slickrock, smooth singletrack, and doubletrack sections built for speed, with rolling hills and punchy climbs throughout and 360 degree views of the Maroon Bells, San Juan Mountains, and the Gunnison Basin. The high desert climate means dry air and real sun exposure, so do not judge the difficulty purely by the elevation profile.
It is a reasonable option if you have technical trail experience, since the slickrock sections demand real footwork and the punchy rolling climbs punish anyone expecting a groomed, runnable course. The roughly 8 hour 15 minute cutoff window gives a well-prepared first-timer real room to finish, and the community feel, Youth Trail Running Initiative and Trail Sisters partnerships, and proceeds going to Gunnison Trails make it a values-aligned choice for a debut ultra.
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<a href="https://runsummitline.com/guides/sage-burner-trail-race">The Sage Burner Trail Race course guide</a>This guide is independent and for planning only. The course details, dates, cutoffs, and aid stations come from public sources and can change year to year, 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.