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⏵ Course guide · Arizona ultra

Old Pueblo 50 Course Guide

The Old Pueblo 50 is one of Arizona’s longest-running ultras, a 50-mile day built as two 25-mile loops out of the historic Kentucky Camp mining site in the Santa Rita Mountains. It runs on Forest Service roads and the Arizona Trail, the climbing is moderate, and the rocky footing is what really gets you. I’ll walk you through the loop first, then give you a pacing and fueling plan that fits the terrain and the cutoffs. There are free calculators along the way to dial in your own numbers.

⏵ At a glance

Old Pueblo 50 quick facts

Date
Saturday, March 7, 2026 (early March)
Location
Kentucky Camp, Santa Rita Mountains, near Sonoita, Arizona
Distances
50 mile (two 25-mile loops) and 25 mile
Elevation gain
50 mile: about 2,500 ft · 25 mile: about 1,570 ft (high point Jerry’s Pass, 6,232 ft)
Start
6:00 AM, with an optional 5:00 AM early start (no awards)
Cutoff
50 mile: 15 hr (first loop by 1:00 PM, plus later checkpoint cutoffs) · 25 mile: 7 hr
Qualifier
Not listed as a Western States, Hardrock, or UTMB qualifier

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 Old Pueblo 50 is won and lost

The 50 is a 25-mile loop you run twice, counterclockwise, on a mix of Forest Service roads and singletrack that includes stretches of the Arizona Trail. About 2,500 feet of climbing total, starting and finishing at Kentucky Camp around 5,142 feet, with the high point at Jerry’s Pass at 6,232 feet. No monster climb, but rocky, rutted trail the whole way.

Loop one: bank patience, not time

The loop opens with a long pull away from Kentucky Camp toward the high ground, and the first aid is several uphill miles in, so you settle into climbing right out of the gate. This early stretch is where people make their big mistake. It feels easy, the legs are fresh, the desert morning is cool, and you run it harder than you should. Do not. The loop has a lot of rocky, rutted footing that quietly taxes your feet and ankles, and what you spend here you do not get back on loop two.

Run loop one well within yourself and arrive back at Kentucky Camp (mile 25) feeling like you are barely working. The first-loop cutoff is 1:00 PM, and most prepared runners clear that with plenty of room, so there is no reason to chase time early. The goal of the first loop is to set up the second one.

Jerry’s Pass and the rolling high desert

The high point is Jerry’s Pass at 6,232 feet, and the course rolls through high desert grassland and oak country in the shadow of the Santa Ritas rather than climbing one sustained grade. That rolling profile is deceptive: there is always a little something to run up, and on tired legs those small rises add up. Keep your effort even over them instead of surging and fading.

The footing stays rocky and rutted in long sections, so quick feet and attention matter as much as fitness. This is a course where you can lose a lot of time and a lot of skin by getting sloppy and clipping rocks late, especially once your form starts to go.

Loop two: the same trail, a different race

Loop two is the whole point. It is the exact same 25 miles, but now it is warmer, more exposed, and your feet are already sore from the first pass over all that rock. Most of the heat management in this race happens after mile 25, because the second loop is usually the warm part of the day. The runners who paced loop one with discipline come through here steady, and the ones who pushed early start doing math on the cutoffs.

Mind the later checkpoint cutoffs on the second loop, commonly around Cave Creek (mile 36) and Melendrez Pass (mile 42). If you trained your feet for rough trail and you kept something in reserve, the second loop is where you reel people in. If you did not, it turns into a long, careful walk to the finish.

Pacing strategy for a two-loop, rocky 50

With moderate climbing spread over rolling, rocky trail and a hard first-loop cutoff, the Old Pueblo 50 is about even effort and clean feet, not hitting a pace chart. Run the rough sections by feel and negative-split the two loops if you can.

Pace by effort, not by your flat splits

Your road pace is useless on rocky, rutted trail. What matters is the steady effort you can hold over the rolling terrain while keeping your feet under control. Hike the steeper pitches without ego and run the runnable sections smooth. The classic Old Pueblo error is running loop one near your flat-ground pace because the climbing is only moderate, then paying for it with a death-march second loop. Use a grade-adjusted pace to turn your real fitness into honest targets for the climbs and the descents so you do not overcook the first 25.

Build a finish prediction, then back it into the cutoffs

Do not guess your Old Pueblo finish off a road 50-mile time. The rocky footing and the warmer second loop both add time that a flat estimate ignores. A vert-aware finish prediction gives you a realistic window, and from there you can work backward into the gates: be through Kentucky Camp by 1:00 PM, then stay ahead of the later checkpoint cutoffs on loop two. Knowing your buffer at each point keeps you from either panicking or coasting into a cutoff.

⏵ Free tools to pace this course

Fueling strategy for a long day on the Arizona Trail

Most runners are out on the Old Pueblo 50 for somewhere around 9 to 14 hours, with the warmer, more exposed stretch coming on the second loop. That makes carbohydrate, sodium, and fluid every bit as important as your legs.

Carbs: steady all day, and trained

For a 9 to 14 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 trap in a long, rough 50 is letting your intake drift down as your feet get sore and your appetite fades, then bonking in the back half. Keep it steady and easy to get down, lean on the aid-station real food (potatoes, fruit, PB&J, soup) when gels stop appealing, and practice your race-day carb rate on long runs so it feels normal, not like an experiment.

Sodium and fluid: plan for a cold start and a warm finish

Early March here can start near freezing and warm up a lot by the afternoon, so your fluid and sodium needs ramp up over the day, especially on the exposed second loop. Lean toward the higher end on sodium as it warms, often around 500 to 700 milligrams per liter of fluid and more if you are a salty or heavy sweater. Carry enough to cover the gaps between aid (the first one is several uphill miles in) rather than rationing to the next one. Weigh yourself before and after a long run to find your real sweat rate, then build the plan around your own number, not a generic one.

⏵ Build your fueling plan

Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and a long Old Pueblo 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 Old Pueblo course profile, and your projected splits. Summit Line reads your real training, builds a plan for the rolling, rocky two-loop 50, and rehearses your fueling so race day is something you execute, not guess at.

Start free →Explore the demo

Old Pueblo 50 FAQ

How hard is the Old Pueblo 50?

It is an honest 50-mile mountain ultra, not a fast course you cruise. The 50 is two 25-mile loops on Forest Service roads and the Arizona Trail in the Santa Rita Mountains, with around 2,500 feet of climbing per the official numbers and a lot of rocky, rutted footing that beats up your feet over a long day. It does not have one giant brutal climb, so the difficulty sneaks up on you through accumulated rough trail and the second-loop heat. With a 15-hour limit it is a finishable goal for a prepared runner, but the cutoffs are real and you have to keep moving.

How much climbing is in the Old Pueblo 50?

The 50 mile has about 2,500 feet of total elevation gain (and the same in descent) across two 25-mile loops, per the official course description. That is moderate for 50 miles, so do not expect a slog of endless climbing, but the gain comes in rolling, rocky ascents and descents rather than smooth grades. The start at Kentucky Camp sits around 5,142 feet and the high point is Jerry’s Pass at 6,232 feet. The 25 mile is a single loop with roughly 1,570 feet of gain.

What are the cutoff times for the Old Pueblo 50?

The 50 mile has an overall limit of 15 hours, but the one that catches people is the first-loop cutoff: you must be back through Kentucky Camp (mile 25) by 1:00 PM to continue onto the second loop. There are later checkpoint cutoffs on loop two as well, commonly around Cave Creek (mile 36) and Melendrez Pass (mile 42), before the 50-mile finish. The 25 mile has a 7-hour limit. Confirm the exact intermediate cutoffs in the current race-day details, since the times can shift year to year.

What is the Old Pueblo 50 course like?

It is a 25-mile loop run counterclockwise, twice for the 50, on a mix of Forest Service roads and singletrack including stretches of the Arizona Trail. The footing is the story: rocky, rutted, and rough in spots, so it rewards strong feet and ankles more than raw speed. You climb out toward Jerry’s Pass and roll through high desert grassland and oak country in the shadow of the Santa Ritas. It is exposed in places and runnable in others, which makes pacing the rough sections the real skill.

What is the weather like at the Old Pueblo 50?

Early March in this part of southern Arizona is all over the map. You can see anything from frost and a cold, dark 6:00 AM start to a warm, sunny afternoon, with temperatures roughly in the 30s to mid-60s Fahrenheit and the occasional chance of rain or even snow. The second loop is usually the warm, exposed part of the day, so most of your heat management happens after mile 25. Pack for both ends of that range and put a layer in a drop bag.

Is the Old Pueblo 50 a good first 50-miler?

It is one of the more reasonable 50-milers to pick as a first one, and it has a long history as an Arizona ultra, but reasonable does not mean easy. The moderate climbing and the 15-hour limit give a prepared first-timer real room, yet the rocky footing and the firm first-loop cutoff still demand specific prep: time on technical trail, a hike-run rhythm you can hold all day, and a fueling plan you have rehearsed. Train your feet and your gut, respect the 1:00 PM gate at mile 25, and it is very doable.

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.