The course
The Mogollon Monster 100 runs up, down, around, and through the Mogollon Rim, the 200 mile escarpment that splits Arizona. The course swings between roughly 5,300 feet on the canyon floor and about 8,000 feet at the top of the Rim, and you pass through changing ecosystems on the way, stitching together the rugged Highline Trail, rocky rim climbs and descents, and stretches of forest road. There is a lot of cumulative climbing here. Published figures land roughly in the 18,000 to 20,000 or more foot range across recent editions.
The Rim is the whole story
The Mogollon Rim rises some 2,000 feet out of the landscape, and the race makes you cross it again and again. You do not get one or two enormous climbs, you get a repeating pattern of steep climbs up onto the Rim and steep descents back down off it, over and over. Each rim climb is a real effort and the descent that follows is rocky and quad-eating, so your legs never get to lock into one steady rhythm.
And that repetition is the whole challenge. Treat every rim climb as a power-hike, not something you try to run, save your legs on the technical descents, and accept that your moving pace is going to swing all over the place. The climbs are not what get you, the descents are. Burn matches on the early climbs and you show up to the back half with nothing left.
The Highline Trail and the technical footing
A long section of the race runs on the Highline Trail, a rugged, rolling singletrack at the base of the Rim. It is constant small ups and downs with no single long sustained climb, and the footing is rocky and technical the whole way. It pays off the runners who move smooth over uneven ground and stay patient instead of fighting it.
And the rest of the course is just as rough: loose rock, roots, steep pitches, trail that makes you pay attention every step. Strong ankles and feet help, and so does some honest practice on technical descents. You cannot zone out and cruise here.
Heat, altitude, night, and monsoon
Early September on the Rim throws a lot at you. The lower canyon elevations can be hot and exposed in the afternoon, the higher Rim country runs cooler, and bouncing between the two is its own kind of stress. The race tops out around 8,000 feet, so if you come from sea level the climbs are going to feel harder than the same grade does at home.
September is also the tail end of Arizona monsoon season, so afternoon thunderstorms, rain, and even cold up high are all on the table, and you will be out for a full night on technical trail. Pack for heat and for cold and wet both, work at keeping your core temperature down in the hot hours, and stay in it mentally through the dark, low-energy night hours. That is when most people drop.
Aid stations and cutoffs
The 100 mile course has a series of aid stations spaced roughly every 5 to 10 miles, with water, electrolyte fluids, food, and medical aid, plus drop bags and crew access at the designated checkpoints. The race starts Saturday morning and runs through the night with a generous overall time limit, which is normal for a rugged mountain hundred.
But several of those checkpoints have firm intermediate cutoffs, and the terrain is too rough to count on making up time late. Pull the official Aravaipa Running aid station and cutoff chart for the current edition, then build your pacing plan backward from those times with a buffer. The repeated climbs, the heat, and the night are all going to slow you down in the second half, so do not plan like they will not.
Pacing strategy for the Mogollon Monster
A course built from repeated rim climbs rewards patience and punishes ego. Run it by effort and by grade, not by the flat-ground numbers from your home training runs.
Pace the rim climbs by grade, not by clock
With repeated steep climbs and roughly 18,000 to 20,000 or more feet of total gain, your moving pace is going to swing hard between the climbs, the rolling Highline, and the descents, and that is fine. That is how it should look. Power-hike the steep rim climbs and only run the gentler grades that are actually runnable. Trying to hold one steady minutes-per-mile number across this terrain is the quickest way to cook the early climbs and blow up late.
Use our free grade-adjusted pace calculator to turn your flat fitness into honest effort targets for the steep Mogollon climbs, so you know whether you are pacing the vertical in a way you can hold, or burning matches you are going to want at mile 80.
Protect your quads for the descents
Every rim climb has a matching steep, rocky descent, and those downhills will shred quads that are not ready for them. Run the early descents controlled and light instead of letting gravity hammer your legs, and your back half is going to be a lot better for it. The runners who finish strong are usually the ones who still have working quads when the late rim descents show up.
To set a finish goal that actually accounts for all that vertical, use our vert-aware race time calculator. It factors the climbing into your projected finish, so you are not stuck on a flat-course estimate that the Mogollon Rim is going to quietly tear apart.
Respect the altitude and the night
The high point near 8,000 feet and the time you spend up on the Rim mean the climbs are going to feel harder than the same grade at sea level, especially if you live low. Run the high sections easy, by your breathing and your effort. Then plan for the night and the cooler temperatures up high. As the afternoon heat backs off your pace can come back, but only if you stayed honest through the hot lower hours and kept eating.
And if you want to know how your fitness from a recent race carries over to a rugged 100 mile mountain effort like this, our race equivalent calculator helps you reality-check the goal before you lock in a finish time.
Fueling strategy for the Mogollon Monster
A hot, rugged, all-day-and-night effort makes fueling and hydration matter as much as fitness. The September heat at the lower elevations is what wrecks most well-trained runners, so plan for it.
Carbs: ramp to the high end, on a trained gut
For an effort this long, aim for roughly 60 to 90 grams of carbohydrate per hour, leaning toward the high end once your gut is trained for it. Use a glucose-plus-fructose blend so you can absorb more than a single sugar lets you, and practice your exact hourly carb number on long runs so that 80 to 90 g/h feels normal by race day, not like an experiment.
The heat makes all of this harder, because a hot stomach handles less. So one more reason to fuel in race-like heat in training, and to keep getting calories in through the ugly hot hours down in the canyons, when your appetite drops but your engine still needs the fuel.
Sodium and fluid: built for the heat
On the exposed Mogollon climbs in early September you can lose a lot of sweat, so push your sodium up, on the order of 500 to 700 mg or more per liter of fluid, and carry enough to cover the rugged, slow gaps between aid stations. Cramping, a sloshy stomach, that wrung-out late-race feeling, those are usually fluid and sodium problems, not fitness problems.
Build a plan with our free ultra fueling calculator. Put in your weight, your goal time, and the heat you expect, and it gives you a carb, sodium, fluid, and caffeine number per hour built for the Mogollon Monster duration and conditions. Then go test it in training.
This guide is for planning and training, and it reflects publicly available information about the Mogollon Monster 100. Race details, including the date, course, distances, aid stations, total elevation gain, and cutoffs, can change year to year, and published vert figures vary by source. Always confirm the current specifics on the official Aravaipa Running race website before you train or travel.