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⏵ Course guide · Vermont ultra

Catamount Ultra Course Guide

The Catamount Ultra is a June staple in Stowe, Vermont, run on the Trapp Family Lodge trail system right at the foot of Mount Mansfield. The 50K is two laps of a rolling, mostly runnable 25K loop, and it has a reputation as a fast, friendly course that still makes you earn it on that second lap. I will walk you through the loop first, then give you a pacing and fueling plan built for the repeating climbs and the early summer warmth. There are free calculators along the way to dial in your own numbers.

⏵ At a glance

Catamount Ultra quick facts

Date
Saturday, June 20, 2026
Location
Trapp Family Lodge, Stowe, VT, at the foot of Mount Mansfield in the Green Mountains
Distances
50K (two 25K loops) and 25K (about 15.5 mi per loop)
Elevation gain
About 2,500 ft per 25K loop, so roughly 5,000 ft for the 50K
Start
50K at 7:00 AM · 25K at 8:30 AM
Cutoff
9-hour overall limit for the 50K, course closes around 4:00 PM
Qualifier
No Western States, UTMB, or Hardrock qualifier status listed by the race

These facts come from the official race site and UltraSignup. Check the current date, cutoffs, and aid stations in the race-day details before you commit. Race logistics change year to year.

The course: where the Catamount is won and lost

The 50K is two full laps of the same 25K loop, about 15.5 miles a lap, circling the Trapp Family Lodge trail system. Figure on roughly 2,500 feet of climbing per loop, so close to 5,000 feet on the day, almost all of it on wide, hard-packed dirt with some forested ski and singletrack mixed in. The whole race comes down to how you run lap one.

The loop: rolling pasture and forest, not one big climb

There is no single monster climb here. The loop rolls. You get short, repeating ups and downs through highland pasture and hardwood forest, past the maple sugar lines strung through the woods, with a few forested ski and singletrack stretches before it opens into farm fields. Individually none of the climbs are scary. Stacked up across a lap they add a real 2,500 feet, and that is the trap: it feels gentle enough early that you run the rises too hard.

Because the footing is mostly friendly and runnable, the Catamount rewards people who can just keep a steady, economical rhythm over rolling ground. This is a course where strong, efficient flat-and-rolling runners do very well, which is why it draws fast New England fields and posts course records.

Lap two is the whole race

Here is the honest truth about a two-lap 50K: the first lap is a warmup and the second lap is the race. Everything that felt easy at mile 5 feels different at mile 20 when you hit the exact same hill with tired legs. The runners who blow up are almost always the ones who banked time on lap one by hammering the rollers, and then watch it bleed back out on lap two.

Run lap one like you have somewhere to be later, because you do. Hike the steeper pitches early even when you feel great, keep the effort honest, and aim to come through the 25K split feeling like you are holding back a little. If you do that, lap two is where you start passing people instead of getting passed.

The loop format is a gift, so use it

One nice thing about a lapped course at the start and finish: you pass through the main aid and your drop bag at the 25K mark, right when you are starting your second lap. That is the moment to reset. Swap a bottle, top off your fluid, grab the calories you stashed, deal with any hot spot on your feet before it becomes a blister, and head back out fueled instead of limping into the back half empty.

Plan that transition before race day so you are not standing around. Know exactly what is in your drop bag and what you grab. A clean, quick reset at the lap is worth more than the minute it costs you.

Pacing strategy for a rolling, two-lap 50K

With about 5,000 feet of climbing spread across a lot of short rollers and a second identical lap waiting, the Catamount is about even effort, not a hot first half. Pace the rises by feel, run lap two off lap one, and you can finish strong.

Run the rollers by effort, not by your flat splits

Your flat-road pace will lie to you on a rolling course like this. What matters is grade-adjusted effort: hold a steady output up the short climbs and let the descents come to you, instead of surging every rise. The classic Catamount mistake is treating the gentle early rollers like a road race and torching your legs before you have even finished lap one. Use a grade-adjusted pace to set honest climb and descent targets off your real fitness, and your two laps end up a lot closer together.

Predict your finish off the vert, then negative-split it

Do not guess your Catamount time off a flat road 50K. The 5,000 feet of rolling climb and the repeated second-lap hills add real minutes, and a vert-aware finish prediction for this course gives you a realistic window to work back from. Then set lap targets from it and aim to run lap two no slower than lap one. On this course, a genuine negative split is very doable and it is how the smart runners finish hours faster than they feel like they are running.

⏵ Free tools to pace this course

Fueling strategy for the duration and the June warmth

Most runners are out on the Catamount 50K for somewhere around 4 to 9 hours, in early summer Vermont warmth that can swing from a cool morning to a humid afternoon. That makes carbohydrate, sodium, and fluid matter as much as the legs do, especially deep into lap two.

Carbs: steady from the start, trained in advance

For a 4 to 9 hour effort, 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 mistake on a friendly course like this is forgetting to eat early because you feel fine, then trying to claw the calories back on lap two when your stomach has gone quiet. Start fueling in the first hour and keep it steady. Practice your exact race-day carb rate on long runs so 70 to 90 grams an hour feels routine, not like a gamble on the day.

Sodium and fluid: scale them to the afternoon

A June morning in the Green Mountains can start cool and turn warm and humid by the time you are grinding out lap two in the afternoon. Plan to take in more sodium and fluid as the day heats up, often in the range of 400 to 700 milligrams of sodium per liter of fluid, and more if you are a heavy or salty sweater. The aid spacing is reasonable, but carry your own bottle and a few of your own calories so a warm, exposed pasture stretch never leaves you empty between stops. Weigh yourself before and after a warm long run to find your real sweat rate, then build the plan around your own number.

⏵ Build your fueling plan

Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and the Catamount warmth 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 Catamount course profile, and your projected splits. Summit Line reads your real training, builds a plan for the rolling climbs and the two-lap format, and rehearses your fueling so race day is something you execute, not guess at.

Start free →Explore the demo

Catamount Ultra FAQ

How hard is the Catamount Ultra?

The Catamount Ultra is an honest mountain ultra but a friendly one as 50Ks go. The 50K is two laps of the 25K loop at the Trapp Family Lodge, mostly wide, hard-packed dirt trail with around 2,500 feet of climbing per loop, so close to 5,000 feet over the full distance. Nothing is brutally technical and nothing is hugely steep, but the rolling climbs add up fast on the second lap, and the 9-hour cutoff is generous enough that a prepared runner who paces the first loop right has real room to finish. It is a great course to run your first 50K or to chase a fast time.

How much climbing is in the Catamount Ultra 50K?

Each 25K loop has roughly 2,500 feet of gain and the same in loss, so the 50K stacks up to about 5,000 feet of climbing and 5,000 feet of descent over the two laps. None of it is a single big mountain. It is rolling highland pasture and forest trail, a lot of short, repeating ups and downs rather than one long grind, which is its own kind of challenge when you hit them all a second time.

What are the cutoff times for the Catamount Ultra?

The 50K has a 9-hour overall time limit, and the race course closes around 4:00 PM. The 50K starts at 7:00 AM and the 25K starts at 8:30 AM. There are no published intermittent cutoffs, but you still want to come through the first 25K loop with comfortable buffer, since the second lop is where tired legs slow down. Confirm the current race-day timing with the official race before you start.

What is the course like at the Catamount Ultra?

It circumnavigates the Trapp Family Lodge trail system at the foot of Mount Mansfield, and it is primarily wide, hard-packed dirt trail rolling through highland pastures and hardwood forest, with maple sugar tap lines through the woods. There are some forested ski and singletrack sections before the course opens into farm fields. The 50K is two full laps of the same 25K loop. The footing is mostly friendly and runnable, which is part of why the course sees fast times and course records from strong New England runners.

How many aid stations does the Catamount Ultra have?

Each 25K loop has three aid stations, at about mile 4.6, about mile 9.4, and one at the 25K start and finish area. The 50K passes through all of them twice since it is two laps, while 25K racers reach two aid stations out on course plus the start and finish. The spacing is reasonable for a course like this, but in June warmth you should still carry your own fluid and a few of your own calories between stops rather than relying only on the aid.

Is the Catamount Ultra a good first 50K?

Yes, it is one of the better first-50K options in New England. The trail is mostly wide and runnable, the climbing is rolling rather than savage, the loop format means you are never far from the start and your drop bag, and the 9-hour cutoff gives most prepared runners plenty of time. Get in some back-to-back long runs and a little rolling vert in training, rehearse your fueling, and respect that the second lap feels a lot longer than the first. Do that and this is a very finishable goal race.

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.