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⏵ Course guide · New Mexico ultra

Cloudcroft Ultra 53K Course Guide

The Cloudcroft Ultra 53K is southern New Mexico’s cool high-country mountain ultra, run almost entirely near 8,600 feet on the historic Rim Trail through fir, pine, and aspen, with big overlooks of the Tularosa Basin far below. It is an out-and-back with a punchier lollipop loop at the turnaround, and the real difficulty is the thin air, not the steepness. I’ll walk you through the course first, then give you a pacing and fueling plan built for racing at altitude. There are free calculators along the way to dial in your own numbers.

⏵ At a glance

Cloudcroft Ultra 53K quick facts

Date
Saturday, August 15, 2026
Location
Cloudcroft, NM · Rim Trail (T105), Lincoln National Forest, Sacramento Mountains
Distances
53K, 9.5 mile, and 4.75 mile (plus a 1-mile kids dash)
Elevation
Runs near 8,600 ft the whole way · rolling rail-bed grade, total gain not officially published
Start times
53K at 7:00 AM · 4.75 mile at 8:30 AM · 9.5 mile at 9:30 AM
Cutoffs (53K)
11-hr limit: 11:00 AM at ~mile 13 (to start the loop), 2:00 PM at ~mile 20, 4:30 PM at ~mile 26, 6:00 PM at ~mile 30
Qualifier
No Western States, UTMB, or Hardrock qualifier status listed by the race

These facts come from the official race site and UltraSignup. The race does not publish a total elevation gain figure, so I kept that general. Check the current date, start times, cutoffs, and aid stations in the race-day details before you commit. Race logistics change year to year.

The course: where Cloudcroft is won and lost

The 53K is an out-and-back on the Rim Trail (T105) with a lollipop loop at the far end, run almost the whole way near 8,600 feet. The trail is mostly shaded single-track and old rail bed through fir, pine, and quaking aspen, so the grades roll instead of wall up. There are six aid stations on the 53K, and because it is an out-and-back you hit the same ones twice.

The altitude is the climb: pace the thin air, not the grade

The thing that actually makes Cloudcroft hard is something you cannot see on a course map: you spend the entire day near 8,600 feet. The rail-bed grades are gentle and runnable, which fools a lot of low-altitude runners into going out too hard early because nothing feels steep. Then the thin air catches up and the back half gets ugly. If you live near sea level, treat the whole first half like a tempo you could hold a conversation through, and let the altitude set your ceiling.

Out and back means the early miles you cruise on the way out are the same miles you grind on the way home. Bank that in your head. The trail itself is friendly, but the air is doing quiet work on you the entire time, so the runners who finish strong are the ones who respected it from the gun.

The lollipop loop: the real vert and the big views

Near the turnaround, the out-and-back opens into a lollipop loop, and this is where the course finally throws some sharper changes in elevation at you, plus the postcard overlooks of the Tularosa Basin more than 4,000 feet below. It is the most interesting and the most demanding stretch of the day. You also have to reach the Alamo Peak area around mile 13 by the 11:00 AM cutoff just to be allowed onto the loop, so the front of the race is not a place to dawdle.

Run the loop by effort, not ego. The views are worth slowing down for, and pushing the punchy bits at altitude here is exactly how people blow their legs and their cutoffs at the same time.

The way home and the cutoffs

After the loop you retrace the Rim Trail back to the finish, and on paper it is runnable, gently descending rail bed. In practice the altitude and the miles have added up, so honest, steady running here is what separates a good day from a death march. The cutoffs keep coming: roughly mile 20 by 2:00 PM, mile 26 by 4:30 PM, and mile 30 by 6:00 PM, with an 11-hour overall limit.

Those intermediate cutoffs mean you cannot save all your buffer for the end. Know what time you need to be through each checkpoint and run the first half with enough margin that the back half is a finish, not a panic.

Pacing strategy for a high-altitude, rolling 53K

Cloudcroft is about managing effort at altitude, not chasing a pace chart. The grades are runnable, so the discipline is resisting the urge to bank time early when the thin air has not bitten yet.

Pace by effort and grade, not by your sea-level splits

Your flat, low-altitude pace will lie to you up here, both because of the thin air and because the rail-bed grades tempt you to run everything. Hold a steady, conversational effort on the way out and hike the punchier bits in the loop without feeling bad about it. The classic Cloudcroft mistake is cruising the gentle early miles too fast because nothing feels hard, then falling off a cliff in the second half. Use a grade-adjusted pace to turn your real fitness into honest targets, then dial the whole thing back a notch for the altitude.

Build a finish prediction you can pace the cutoffs against

Do not guess your Cloudcroft finish off a road 50K time. Altitude, the rolling profile, and trail footing all add real minutes, and you have four hard intermediate cutoffs to clear. A finish prediction that accounts for this course gives you a realistic window, and then you can work backward into each checkpoint so you know exactly how much margin you have at miles 13, 20, 26, and 30 instead of finding out the hard way.

⏵ Free tools to pace this course

Fueling strategy for altitude and a long day

Most runners are out on the Cloudcroft 53K for somewhere around 5 to 11 hours, and the altitude messes with your gut. That makes steady carbohydrate, sodium, and fluid just as important as fitness.

Carbs: steady, trained, and easy to get down

For a 5 to 11 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. Altitude tends to blunt appetite and slow digestion, so the trick at Cloudcroft is keeping intake steady and swallowable from the start rather than gambling on big late doses when your stomach has already checked out. Practice your exact race-day carb rate on long runs so 70 to 80 grams an hour feels routine, not like an experiment.

Sodium, fluid, and the six aid stations

There are six aid stations on the 53K, stocked with sport drink, water, gels, and the usual chips, pretzels, and candy, and you hit them twice on the out-and-back. That is generous coverage, but I would still carry enough fluid to ride out the gaps comfortably rather than running dry between them. The mountain air feels cool and dry, which can hide how much you are sweating, so do not under-drink just because you are not roasting. Weigh yourself before and after a long run to find your real sweat rate, then set sodium and fluid 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 a long day at altitude 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 Cloudcroft course profile, and your projected splits. Summit Line reads your real training, builds a plan for racing at altitude, and rehearses your fueling so race day is something you execute, not guess at.

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Cloudcroft Ultra 53K FAQ

How hard is the Cloudcroft Ultra 53K?

It is a real mountain ultra, but the difficulty here is altitude and duration more than brutal climbing. The whole 53K sits near 8,600 feet on the Rim Trail in the Sacramento Mountains, so the air is thin and the grades are mostly the gentle, rolling kind you get on an old rail bed, with a punchier lollipop loop at the turnaround. If you live near sea level, that elevation is the thing that will surprise you. The overall limit is 11 hours with four hard intermediate cutoffs, so steady effort and not redlining the early miles at altitude matter more than raw speed.

How much climbing is in the Cloudcroft Ultra 53K?

The race does not officially publish a total elevation gain figure, so I am not going to make one up. What I can tell you is the character: it is an out-and-back on the historic Rim Trail (T105), a rail-bed style trail, so the grades are mostly rolling and runnable rather than steep wall climbs. The real vert lives in the lollipop loop near the turnaround, where the course throws in some sharper changes and the big overlooks of the Tularosa Basin more than 4,000 feet below. Treat it as honest rolling terrain at high altitude, and confirm the current profile on the race GPX before race day.

How should I fuel for the Cloudcroft Ultra 53K?

Plan for a roughly 5 to 11 hour day at altitude, which changes how your gut behaves. Most runners do well on around 60 to 90 grams of carbohydrate per hour, but thin air at 8,600 feet can blunt your appetite and slow digestion, so keep intake steady and easy to swallow instead of forcing big late doses. There are six aid stations on the 53K, but you still want to carry enough fluid and calories to ride out the gaps comfortably. Run your numbers for your weight and goal time with the free ultra fueling calculator and rehearse them on long runs.

What are the cutoff times for the Cloudcroft Ultra 53K?

The 53K has an 11-hour overall limit off the 7:00 AM start, with four intermediate cutoffs you have to make. You need to reach the Alamo Peak area around mile 13 by 11:00 AM to start the lollipop loop, be done with the loop near mile 20 by 2:00 PM, hit roughly mile 26 by 4:30 PM, and roughly mile 30 by 6:00 PM. Those checkpoints mean you cannot bank all your buffer for the finish. Confirm the exact cutoffs in the current race-day details before you start, since times shift year to year.

What is the terrain and weather like at the Cloudcroft Ultra?

The trail is mostly shaded single-track and old rail bed winding through stands of fir, pine, and quaking aspen, with high-elevation overlooks of the Tularosa Basin. Footing is generally runnable but it is still mountain trail, so expect roots, rock, and some looser sections in the lollipop loop. The big draw is that Cloudcroft is genuinely cool high country in August, which is why a summer 53K up here is so popular when the desert below is baking. That said, mountain weather is moody: afternoon thunderstorms, sun, and temperature swings are all on the table, so pack for more than just heat.

Is the Cloudcroft Ultra 53K a good first 53K?

It can be a great first ultra for a prepared runner, and the shaded, rolling, mostly runnable trail is friendlier than a lot of steep mountain 50Ks. The catch is the altitude. Racing 33 miles near 8,600 feet is a real ask if you live low, so the smart move is to arrive a few days early to adjust if you can, start conservatively, and respect the cutoffs. If you train your long runs, rehearse your fueling, and pace the early miles like the altitude is real, the 11-hour limit gives most committed first-timers room to finish.

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, 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.