Siskiyou Out Back Course Guide

The 50K: the original, and still the one most people run

The 50K is about 30.8 miles with roughly 4,900 feet of climbing, and it has anchored this race for over 20 years. You start down at the Mt. Ashland ski area lot at 7:00 AM, run a big loop out along the Crest on a mix of PCT, fire road, and singletrack, and finish back up at the Mt. Ashland Lodge at the high point of the course near 7,500 feet. There are four aid stations along the way (Willamette Meridian near 5.9 miles, Siskiyou Gap near 10 miles, Jackson Gap near 15.7 miles, and Siskiyou Gap again near 21.7 miles), and a couple of them you hit twice, so plan your drop bags around that.

This is not a course that punishes you with one giant wall. It is rolling, high, and exposed, and the trap is treating the runnable early road like a road race. Run the first half by feel and you arrive at that final Mt. Ashland climb with legs. Hammer the early gradual stuff because the altitude masks how hard you are working, and that last pull to the lodge gets very long.

The 100K: double the day, and the altitude starts to bite

The 100K is about 60.4 miles with roughly 10,500 feet of gain, starting from the Mt. Ashland Lodge at 5:00 AM with an 18-hour limit. You cover more of the Crest and tag bigger high points, including McDonald Peak and Big Red Mountain on top of Mt. Ashland itself, across nine aid stations. The extra distance means you are out in the high, dry air far longer, and the back half is where the altitude and the cumulative climbing start to add up in your legs and your stomach.

Pace this one like a long day, not a stretched 50K. The people who finish strong are the ones who keep eating and drinking early, walk the climbs with purpose, and treat the sun as a real opponent rather than a backdrop. If you let yourself get behind on fluid or calories in the first 30 miles up here, you do not claw it back.

The Brink 100: town to summit, three peaks, and a long night

New for 2026, the Brink 100 is a true mountain hundred, roughly 100.2 miles with about 22,800 feet of climbing. It starts down on the Plaza in downtown Ashland at 4:20 PM on Friday and climbs its way up to finish with everyone else at the Mt. Ashland Lodge, tagging three summits above 7,000 feet along the way: Wagner Butte, Dutchman Peak, and Mt. Ashland. With a town start in the late afternoon, you are climbing into the first night almost immediately, so your headlamp game and your night-running nerves matter from the very start, not just at mile 70.

Because the clock runs about 38 hours and 40 minutes, most people will see two nights out there. That changes everything: sleepiness, the deep low that hits in the small hours, body temperature swings between the warm exposed climbs and the cold high ridgelines after dark. Layers you can actually reach, a plan for the 3 AM lows, and a willingness to keep moving when your brain wants to quit are what get you to that final Mt. Ashland climb with a finish in hand.

Crew, drop bags, and pacers on the 100

On the Brink 100 you get drop bags, crew access, and pacers, but pacers are only allowed after the Sterling Mine aid station near mile 42.8, so the first stretch through the first night is on you. Build your drop bags for a two-night race: spare headlamp and batteries, warm layers for the cold high ridges after dark, sun protection for the exposed daytime climbs, and the exact food your gut tolerates when it is tired and high. Brief your crew on the intermediate cutoffs (Sterling Mine, Bear Gulch, Wrangle, Siskiyou Gap) so they keep you honest and moving instead of letting an aid station turn into a nap you did not plan.

Treat aid stations like quick pit stops with a checklist, not lounges. On a course this long and this exposed, ten wasted minutes per stop adds up to a missed cutoff, and the warm chair at 3 AM is the most dangerous thing out there. Know what you need before you arrive, grab it, and go.

Altitude, sun, and the gaps between aid

The single biggest thing that humbles flatland runners here is not one climb, it is the combination of altitude and exposure across the whole Crest. A lot of this course sits above 6,000 feet, the air is thin and dry, and the July sun on those open PCT ridgelines is relentless. If you live at sea level, your goal pace will feel harder than the numbers say, so plan to run by effort and give yourself grace on the climbs.

The stretches between aid can be long and sun-baked, so carry enough fluid and calories to cover them rather than rationing to the next station and showing up empty. Make heat, sun, and altitude part of your plan from the gun, not something you react to when it is already cooking you.

Pace the climbs by grade, not by the watch

Your flat-ground pace means nothing on the long climbs along the Siskiyou Crest, and it means even less at 6,000-plus feet. What matters is grade-adjusted effort, so hold a steady output you can keep up the grade and hike the steep pitches without feeling bad about it. The classic mistake here is running the runnable early road too hard because the altitude hides the cost, then fading on the back half and the final Mt. Ashland climb. Use a grade-adjusted pace to turn your real fitness into honest climbing and descending targets, and you will not torch the first half.

Build a vert-aware finish prediction

Do not guess your SOB finish off a road marathon or a flat 50K time. The climbing, the altitude, and the exposed sun all add real minutes, and the longer distances compound it. A vert-aware finish prediction that accounts for this course profile gives you a realistic window and lets you work back into the cutoffs, so on the 100K and the Brink 100 you actually know how much buffer you have at each checkpoint instead of finding out the hard way at Sterling Mine or Wrangle.

Carbs: steady and trained

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 and sun both kill your appetite and slow your stomach down, so keep intake steady and easy to get down instead of gambling on big late doses, especially deep in the 100K or the Brink 100 when you are tired and high. Practice your exact race-day carb rate on hot, long climbs so 80-plus grams an hour feels normal, not like an experiment you are running for the first time on the Crest.

Sodium and fluid: plan for the dry air and the gaps

In the heat and the dry mountain air, lean toward the high end on sodium, often around 500 to 700 milligrams per liter of fluid, and more if you are a heavy or salty sweater. Just as important, carry enough fluid to cover the long, exposed stretches between aid stations rather than rationing to the next one and arriving empty. Weigh yourself before and after a hot long run to find your real sweat rate, then build the plan around your own number instead of a generic guess.