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⏵ Course guide · Northern Colorado trail weekend

Red Feather Trail Jamboree Course Guide

Gnar Runners' Red Feather Trail Jamboree spreads three races across three days at Ben Delatour Scout Ranch near Red Feather Lakes: a 50 Mile Friday, a 50K Saturday, and a Half Marathon Sunday, run alone or together. I will walk you through the weekend's format and each day's course first, then give you a pacing and fueling plan built for northern Colorado's high country. There are free calculators along the way to dial in your own numbers.

⏵ At a glance

Red Feather Trail Jamboree quick facts

Dates
Friday-Sunday, September 25-27, 2026
Location
Ben Delatour Scout Ranch, Red Feather Lakes, Colorado
Format
50 Mile (Fri), 50K (Sat), Half Marathon (Sun), enter any single day or all three as the 3-Day Challenge
Vertical gain
50 Mile: ~8,500 ft · 50K: ~4,200 ft · Half Marathon: ~1,700 ft
Elevation range
7,350 to 10,828 ft (50 Mile) · 7,350 to 8,500 ft (50K / Half)
Terrain
70-80% singletrack, 20-30% dirt road, through Boy Scout property and national forest
Start times
50 Mile: Fri 6:00 AM · 50K: Sat 7:00 AM · Half Marathon: Sun 8:30 AM
Time allowance
50 Mile: 16 hr · 50K: 11 hr, no intermediate cutoff · Half: 6 hr, no intermediate cutoff
Cutoff
One cutoff on the 50 Mile: Granite Ridge Aid Station (mile 32.4) by 4:30 PM
Field cap
500 runners total across the weekend

These facts come from the official Gnar Runners race page. Check the current year details, cutoffs, and aid stations before you commit. Race logistics change year to year.

The weekend: three days, three courses

Each day of the Jamboree is its own race with its own course, so treat this as a schedule of three events rather than one race with a long distance. Sign up for whichever day fits your goals, or all three for the 3-Day Challenge.

Friday: the 50 Mile, five trail systems and one cutoff

The 50 Mile starts at 6:00 AM and combines five different trail systems within the National Forest and Boy Scout property, climbing to a high point just under Middle Bald Mountain in the Laramie Mountains. It carries about 8,500 feet of gain and the weekend's only intermediate cutoff, at Granite Ridge (mile 32.4) by 4:30 PM, built to get runners back on camp property before dark while still guaranteeing at least a 50K finish. The overall time allowance is 16 hours.

Saturday: the 50K, technical early miles into flowing forest

The 50K starts at 7:00 AM with about 4,200 feet of gain. The first 10 miles are more technical before the course connects with flowing, runnable trails inside the National Forest Service system. There is no intermediate cutoff, only the 11-hour overall time allowance, so a steady, patient pace has real room to work with here.

Sunday: the Half Marathon, the accessible closer

The Half Marathon starts at 8:30 AM and is mostly smooth dirt with moderate climbs, about 1,700 feet of gain total. Like the 50K, there is no intermediate cutoff, just the 6-hour overall window. It is the easiest access point into the weekend, and for 3-Day Challenge runners, it is also the day your legs will feel every mile of the previous two.

Pacing strategy for one day or all three

Whether you are running a single day or the full 3-Day Challenge, elevation between 7,350 and 10,828 feet changes what an honest effort feels like from the first mile.

Respect the altitude from mile one

A grade-adjusted pace target built for high-altitude climbing gives you an honest number for what is sustainable at 8,000 to 10,000-plus feet, which is almost always slower than what the same grade would demand near sea level. This matters most on Friday's 50 Mile, where the Granite Ridge cutoff punishes anyone who banks time by going out too hard early and paying for it in oxygen debt later.

If you are doing all three days, plan the recovery, not just the race

A vert-aware finish prediction for each day, checked against that day's time allowance, tells you whether your pacing plan actually works, not just whether it feels reasonable on paper. For the 3-Day Challenge specifically, build in real recovery between days: sleep, food, and easy walking matter as much as your in-race pacing decisions.

⏵ Free tools to pace this weekend

Fueling strategy across a mountain weekend

Late September in the Red Feather Lakes area brings cool mornings and warmer afternoons at real altitude, and a multi-day weekend adds recovery nutrition to the equation.

Carbs: steady on race days, deliberate between them

Aim for roughly 60 to 90 grams of carbohydrate per hour on the 50 Mile and 50K, using the aid stations spaced every 5 to 7 miles to stay consistent. If you are running multiple days, treat the hours after each race as part of the plan: real food and carbohydrate replacement between days directly affects how the next day's legs feel.

Sodium: scale with the day\'s heat and altitude

Sodium in the 300 to 700 mg per liter range covers most runners, leaning higher on any day that runs warm or exposed. Altitude and dry mountain air both increase fluid loss you may not notice as sweat, so do not wait for obvious thirst to start drinking.

⏵ Build your fueling plan

Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and high-altitude Colorado terrain 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, whichever Red Feather day (or all three) you are targeting, and your projected splits at altitude. Summit Line reads your real training, builds a plan for high-country climbing, and rehearses your fueling so race weekend is something you execute, not guess at.

Start free →Explore the demo

Red Feather Trail Jamboree FAQ

How does the Red Feather Trail Jamboree weekend work?

It is three separate races on three consecutive days at Ben Delatour Scout Ranch near Red Feather Lakes: a 50 Mile on Friday, a 50K on Saturday, and a Half Marathon on Sunday. You can enter any single day on its own, or sign up for the 3-Day Challenge and run all three. Each distance has its own start time, course, and entry fee, so treat it as three races that happen to share a venue and a weekend, not one long event.

How much climbing is in the Red Feather Trail Jamboree?

The 50 Mile carries about 8,500 feet of vertical gain and tops out just under Middle Bald Mountain in the Laramie Mountains, with elevation ranging from 7,350 to 10,828 feet. The 50K covers about 4,200 feet of gain within the 7,350 to 8,500 foot band, and the Half Marathon is the mellowest day at roughly 1,700 feet on mostly smooth dirt with moderate climbs. If you are doing the 3-Day Challenge, the cumulative fatigue across all three days matters more than any single day's vert.

How should I fuel for the Red Feather Trail Jamboree?

Late September in northern Colorado at 7,000 to 10,000-plus feet can swing from cold mornings to warm afternoons, so plan your fueling and sodium to shift across each day. Aim for roughly 60 to 90 grams of carbohydrate per hour on the 50 Mile and 50K, and sodium in the 300 to 700 mg per liter range, leaning higher if the day runs warm. Full-service aid stations stock Gnarly Fuel2O sports drink, water, salty snacks, fruit, and sweets, spaced every 5 to 7 miles depending on the day. If you are running all three days, do not treat any single day's fueling in isolation, recovery nutrition between days matters as much as what you eat mid-race. Build your numbers with the free ultra fueling calculator before race day.

What are the cutoffs for the Red Feather Trail Jamboree?

The 50K and Half Marathon have no intermediate cutoffs at all: anyone who completes the full course within the overall time allowance, 11 hours for the 50K and 6 hours for the Half, is a finisher. The 50 Mile is different: it carries one cutoff, at the Granite Ridge Aid Station (mile 32.4) by 4:30 PM, put in place so runners are back on camp property before dark while still guaranteeing at least a 50K finish for anyone who reaches it. The overall 50 Mile time allowance is 16 hours from its 6:00 AM Friday start.

What is the terrain like at Red Feather Trail Jamboree?

Expect 70 to 80 percent singletrack and 20 to 30 percent dirt road across five different trail systems on Boy Scout property and surrounding national forest. The 50K opens with more technical terrain over its first 10 miles before connecting to flowing, runnable Forest Service trails, while the 50 Mile adds a high point near Middle Bald Mountain through moose-heavy forest, fields, streams, and rocky sections. Wildlife here is real: moose, elk, mule deer, black bears, and mountain lions all share this range, so stay aware, especially in early morning starts.

Is the Red Feather Trail Jamboree a good first ultra?

The Half Marathon and 50K days are genuinely approachable: no intermediate cutoffs, generous overall time allowances, and a repeated-access venue at Ben Delatour Scout Ranch with camping, cabins, and a community dinner on site. The 50 Mile is a bigger step, with real high-altitude vert and one hard cutoff at mile 32.4, so a first-time ultra runner is better served picking the Saturday 50K or Sunday Half than jumping straight into the full 3-Day Challenge.

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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.