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⏵ Course guide · California ultra

Sierra Crest 50K Course Guide

The Sierra Crest 50K is a point-to-point run on some of the best singletrack in the Northern Sierra, climbing out of Tahoe Donner near Truckee and crossing the crest to finish at the Auburn Ski Club up on Donner Summit. It is famous for being sweet and runnable, but do not let that fool you: it is stacked with climbs, it lives up near and above 7,000 feet, and there is a hard cutoff at Donner Lake you have to beat. I will walk you through the course first, then give you a pacing and fueling plan that fits the climbing and the altitude. Free calculators along the way to dial in your own numbers.

⏵ At a glance

Sierra Crest 50K quick facts

Date
Early August (typically the first Saturday); confirm the current year with the race
Location
Point-to-point, Tahoe Donner near Truckee to the Auburn Ski Club at Donner Summit / Soda Springs, CA
Distances
50K (about 31 mi) · 30K (about 18 mi) · 15K
Elevation gain
50K: about 4,660 ft gain / 4,125 ft loss · 30K: about 3,493 ft gain / 2,948 ft loss
Start / finish
Start Alder Creek Adventure Center (about 6,650 ft), finish Auburn Ski Club Training Center (about 7,200 ft)
Cutoff
50K: hard 1:30 PM cutoff at the Donner Lake aid station, strictly enforced; confirm the current start times and any other cutoffs
Qualifier
No Western States, Hardrock, or UTMB qualifier status listed by the race

These facts come from the race host pages and UltraSignup. 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 Sierra Crest is won and lost

The 50K is a true point-to-point, about 31 miles with roughly 4,660 feet of climbing and 4,125 feet of loss as you cross the crest of the Sierra Nevada. You start on the trails at Tahoe Donner around 6,650 feet, work up and over onto the Donner Lake Rim Trail, and finish on the Auburn Ski Club trails up at about 7,200 feet. It is not one big climb. It is a long string of them, and the trail underfoot is some of the most runnable you will find.

The opening climbs: Tahoe Donner up to Hawk's Peak

You leave the corrals at Tahoe Donner on flat horse trails through the trees (watch for roots and, yeah, a little manure), and then the course tips up at Boot Hill and starts climbing. The early grind goes up broad, exposed trail past markers and switchbacks toward Hawk’s Peak, which tops out around 7,600 feet and is the longest sustained climb of this part of the course. This is where the day gets decided. The footing is rocky and the sun is already up, so hike the steep pitches efficiently, keep your effort even, and resist the urge to hammer just because your legs feel fresh.

Once you are up high the reward kicks in: big views of Martis Valley, Castle Peak coming into sight, alpine meadows and granite. But you are also up at altitude now, so the thin air is taxing your climbing pace whether you feel it yet or not. Run the climbs a notch easier than your flat fitness says, especially if you live at sea level.

The runnable middle: smooth singletrack and the rim

This is the stretch the race is known for. Sections like Glacier Way and the Donner Ridge run on pristine, groomed cross-country ski trail with almost no roots or loose rock, so they are flat-out fast if you have legs for them. You roll along the Donner Lake rim with views of Tinker’s Knob and Mount Judah, past the Frog Lake Cliffs and Euer Valley, and the miles can click by quicker than you expect. The temptation here is to overcook the runnable bits and forget there is still climbing and a long descent ahead.

Be smart: this is the part of the course where you make up time without wrecking yourself. Stay smooth, keep eating, and keep one eye on the clock so you hit the Donner Lake aid station with margin on that 1:30 PM cutoff.

The Donner Lake cutoff and the run to the finish

The Donner Lake aid station carries a hard 1:30 PM cutoff that the race enforces strictly, so this is the checkpoint that defines your whole pacing plan. You cannot save all your buffer for the end here. From there the course climbs back up and over toward the Auburn Ski Club at Donner Summit, with some rocky, exposed terrain and that final push to about 7,200 feet at the finish.

The late miles are where altitude and the stacked climbing add up. If you paced the opening climbs honestly and kept fueling, you will have the legs to run the last runnable sections and close strong. If you went out hard up Hawk’s Peak, the thin air and the final climbs will make those last miles a grind.

Pacing strategy for a runnable, high-altitude 50K

With about 4,660 feet of gain spread across stacked climbs, a lot of genuinely fast trail in between, and a hard cutoff at Donner Lake, Sierra Crest is about managing effort and time, not chasing a flat pace chart. The altitude is the variable most people underrate.

Pace the climbs by grade, not by the watch

Your flat-ground pace means nothing on the climb up to Hawk’s Peak, and it means even less at 7,500 feet. What matters is grade-adjusted effort: hold a steady output you can sustain up the grade, and hike the steep pitches without feeling bad about it. The classic Sierra Crest mistake is running the runnable opening too hard because the trail is so good, then paying for it on the back-half climbs. Use a grade-adjusted pace to turn your real fitness into honest climbing targets, and shave a little extra off for the thin air.

Build a finish prediction that respects the cutoff

Do not guess your Sierra Crest finish off a road 50K time. The 4,660 feet of climbing, the altitude, and the point-to-point profile all change the math. A vert-aware finish prediction gives you a realistic window and, just as important, lets you work backward into the 1:30 PM Donner Lake cutoff so you know exactly what pace gets you there with margin instead of finding out the hard way.

⏵ Free tools to pace this course

Fueling strategy for altitude and the duration

Most runners are out on the Sierra Crest 50K for somewhere around 5 to 9 hours, in the warm August sun and up at altitude where your stomach is fussier than usual. That makes carbohydrate, sodium, and fluid every bit as important as fitness.

Carbs: steady, and don't let altitude shrink them

For a 5 to 9 hour effort, aim for roughly 60 to 90 grams of carbohydrate per hour, leaning to the higher end only if your gut is trained for it. Altitude tends to blunt your appetite and slow your stomach, so the trap here is quietly eating less than you planned and bonking late. Keep intake steady and easy to get down, and practice your exact race-day carb rate on long runs (at elevation if you can get there) so it feels normal and not like an experiment on race morning.

Sodium and fluid: plan for sun and the aid spacing

August up here is warm with strong high-altitude sun, so lean toward the higher end on sodium, often around 500 to 700 milligrams per liter of fluid, and more if you are a heavy or salty sweater. The 50K has five aid stations across roughly 31 miles, and several pass through crew-accessible spots, but a couple of the gaps run long and exposed, so carry enough fluid to cover them rather than rationing to the next one. Weigh yourself before and after a hot 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 Sierra Crest conditions 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 Sierra Crest course profile, and your projected splits. Summit Line reads your real training, builds a plan for the stacked climbs and the altitude, and rehearses your fueling so race day is something you execute, not guess at.

Start free →Explore the demo

Sierra Crest 50K FAQ

How hard is the Sierra Crest 50K?

It is a real mountain 50K, but a friendlier one than most. The 50K runs about 31 miles with roughly 4,660 feet of climbing on some of the most runnable singletrack in the Northern Sierra, point to point from Tahoe Donner over the crest to Donner Summit. The catch is altitude: you start around 6,650 feet and spend the whole day up near and above 7,000, so the air is thin and the exposed climbs cook in the August sun. The trail itself rewards honest fitness, and the strictly enforced 1:30 PM cutoff at Donner Lake is the number you have to respect.

How much climbing is in the Sierra Crest 50K?

The 50K has about 4,660 feet of total gain and about 4,125 feet of loss over roughly 31 miles, so it climbs a touch more than it drops on its way over the Sierra crest. There is no single monster climb; it is a series of stacked climbs, the longest of which tops out around Hawk’s Peak near 7,600 feet, then rolling high country and a net descent toward Donner Lake and the finish. The 30K is shorter at about 18 miles with roughly 3,493 feet of gain, following the first part of the same course.

What is the cutoff for the Sierra Crest 50K?

The one to plan around is a hard 1:30 PM cutoff at the Donner Lake aid station, and the race enforces it strictly, so if you are behind it there you are done. That means you cannot bank all your time for the back half; you have to keep moving through the early climbs to reach Donner Lake with margin. Start times have shifted between years, so check the current start time and any additional intermediate cutoffs in the race-day details before you toe the line.

What is the terrain and weather like at Sierra Crest?

This race is known for sweet, runnable trail. Most of it is buttery Sierra singletrack and groomed cross-country ski trails through pine forest, granite, and alpine meadows, with named segments like Boot Hill, the Donner Lake Rim Trail, and Glacier Way, plus views of Castle Peak and the Frog Lake Cliffs. Footing ranges from pristine and smooth to loose and rocky on the exposed climbs. Early August up here is usually warm and dry with strong high-altitude sun, but mountain weather is mountain weather, so an afternoon storm or a cool morning is always on the table.

Does altitude matter at the Sierra Crest 50K?

Yes, more than the vert numbers suggest. You start around 6,650 feet and the course climbs to roughly 7,600 feet, so you are above 7,000 feet for most of the day. If you live near sea level, your climbing pace and your stomach will both feel the thin air, and pushing too hard early at altitude is a fast way to blow up. Arriving a few days early to acclimate helps, and if you cannot, just plan to run the climbs a notch easier than your fitness says you should.

Is the Sierra Crest 50K a good first 50K?

It is one of the better mountain 50Ks to pick as a first ultra, mostly because the trail is so runnable and the scenery carries you along. That said, the climbing, the altitude, and the firm 1:30 PM Donner Lake cutoff still ask for specific prep: time on climbs, practice running smooth descents on tired legs, and a fueling plan you have rehearsed. Train the climbs and respect the altitude and most prepared first-timers can absolutely finish this one.

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.