⏵ Course guide · Centennial Trail out-and-back
The Black Hills 100 runs an out-and-back on the Centennial Trail from Sturgis, South Dakota, 16,779 feet of gain and loss on dirt, rock, and mixed single and double-track. What the Black Hills lack in altitude, the race directors say, they make up for in relentless hills. I will walk you through the up-then-down terrain first, then give you a pacing and fueling plan built for constant elevation change, plus free tools to dial in your own numbers.
These facts come from the official Black Hills 100 race site. Aid station details and crew access rules can change year to year, so confirm the current specifics on blackhills100.com before you commit.
The 100 mile race runs out and back on the Centennial Trail (Trail #89) and Deerfield Trail (Trail #40), starting and finishing at Sturgis City Park. The race directors describe the elevation profile in four words: "Up. Then down. Then up again. Repeat."
Unlike a lot of western hundreds, Black Hills 100 does not rely on thin air to make things hard. The course tops out at modest elevation for a mountain race, and instead delivers 16,779 feet of gain and loss through relentless rolling terrain, dirt, rocks, and a mix of single-track and double-track ATV trail. The difficulty is cumulative, not altitudinal.
Because the course is out and back from Sturgis, you cover every mile twice, once on the way out and once heading home. That gives you a direct comparison point: the climb that felt manageable outbound will feel very different on tired legs during the return, so plan your effort with that second pass in mind from the start.
Average late June conditions in Sturgis run a high near 79 degrees and a low near 53, with a chance of afternoon thunderstorms. With a Friday 10:00 am start and a 34 hour cutoff, most 100 mile runners experience both the warm part of at least one afternoon and a full cool night, so pack for both extremes.
With 16,779 feet of gain and loss and a 34 hour cutoff from a Friday 10:00 am start, this is a course where a flat-ground pace target will mislead you badly.
Because the elevation profile is constant up-and-down rather than one long climb, a grade-adjusted pace target matters on nearly every mile of this course, not just a handful of named ascents. Set an honest number for the rolling terrain and hold it, rather than surging on the downhills and losing time on every climb that follows.
Your outbound pace on this out-and-back gives you real data for the return trip, but expect the second half to run slower given accumulated fatigue on the same climbs. A vert-aware finish prediction built off your outbound split, adjusted honestly for fatigue, is a far better guide than assuming symmetric splits out and back.
⏵ Free tools to pace this course
A Friday 10:00 am start and a 34 hour cutoff mean most 100 mile runners are out through a warm afternoon, a full cool night, and well into a second day.
Aim for roughly 60 to 90 grams of carbohydrate per hour across the full race. With a 34 hour window, consistency matters more than any single big feed, so build a per-hour target you can actually sustain through both the warm afternoon push and the long overnight stretch.
Sodium in the 300 to 700 mg per liter range covers most runners, leaning toward the higher end during the warm afternoon hours given the average late-June high near 79 degrees and the chance of afternoon thunderstorms. Dial back toward the lower end once temperatures drop overnight.
⏵ Build your fueling plan
Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and a warm-day, cool-night Black Hills race 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 constant rolling Black Hills climbing profile, and your projected splits. Summit Line reads your real training, builds a plan for cumulative elevation change, and rehearses your fueling so race day is something you execute, not guess at.
Black Hills 100 is a genuinely tough hundred despite its modest starting elevation. The race's own organizers put it plainly: "What the Black Hills lack in altitude, they make up for in relentless hills that offer a unique challenge compared to other western ultras." With 16,779 feet of gain and loss on an out-and-back Centennial Trail course, dirt, rocks, and mixed single-track and double-track terrain, and a 34 hour cutoff, the difficulty here comes from constant elevation change rather than thin air or one big climb.
The official race site lists 16,779 feet of elevation gain and loss for the 100 mile distance. The organizers describe the elevation profile simply: "Up. Then down. Then up again. Repeat." That constant rolling character, rather than any single mountain, is what makes Black Hills 100 harder than the raw mileage suggests.
With a 34 hour cutoff from a Friday 10:00 am start, plan for at least one full night on the Centennial Trail and likely into a second day. Late June in the Black Hills averages a high near 79 degrees and a low near 53, with a chance of afternoon thunderstorms, so plan for warm afternoon miles and cooler overnight running. Aim for roughly 60 to 90 grams of carbohydrate per hour, and sodium in the 300 to 700 mg per liter range, leaning higher through the warmer afternoon stretches. Build your numbers with the free ultra fueling calculator before race day.
The 100 mile cutoff is 34 hours from the Friday 10:00 am start. The shorter distances have their own cutoffs: 14 hours for the 50 mile, 12 hours for the 50K, and 11 hours for the 30K, each starting Saturday from a different point along the trail. Given the 16,779 feet of gain and loss on the 100 mile course, build real margin into your pacing plan rather than treating 34 hours as a comfortable buffer.
It is a solid choice for a runner with real trail and hill-climbing experience, less so for someone new to sustained elevation change. The course rewards a runner who has trained on rolling, repeated climbing rather than flat or single-mountain terrain, since the Black Hills 100 profile is exactly that: constant up and down rather than one defining ascent. The out-and-back format also means you retrace your own steps on the return, which gives a first-timer a psychological landmark, you have already covered this ground once, even on tired legs the second time through.
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<a href="https://runsummitline.com/guides/black-hills-100">The Black Hills 100 course guide</a><iframe src="https://runsummitline.com/embed/race/black-hills-100" style="width:100%;max-width:420px;height:180px;border:0;" loading="lazy" title="Black Hills 100 course guide by Summit Line"></iframe>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.