⏵ Course guide · Sheyenne National Grasslands, North Dakota
END-SURE, the Extreme North Dakota Sandhills Ultra Run Experience, sends you point-to-point on the North Country Trail across the entire Sheyenne National Grasslands, prairie, forest pockets, and rolling sandhills, about 45 minutes southwest of Fargo. I will walk you through the 25K, 50K, and 100K options, then give you a pacing and fueling plan for a race with real exposure and very little shade. There are free calculators along the way to dial in your own numbers.
These facts come from the official END Racing event page. Check the current year details before you commit. Race logistics can change year to year.
Unlike a lot of ultras that loop back to a central hub, END-SURE runs point-to-point on the North Country Trail across the entire Sheyenne National Grasslands, so the terrain changes character as you move through it rather than repeating.
The official course description calls out wide open prairie, pockets of forest, and rugged, rolling "sandhills" as the defining terrain. That mix means long exposed stretches with real wind and sun exposure alongside shadier, more sheltered sections, so your fueling and clothing plan needs to flex across very different microclimates in the same run.
The 25K, 50K, and 100K all start together at 7am from Jorgen's Hollow Campground near McLeod. The 25K and 50K share a 10 hour window (cutoffs at 6pm and 5pm respectively), while the 100K gets a 16 hour window with an 11pm cutoff, meaning 100K runners should plan for hours of running in the dark if they are anywhere near the back of that window.
END-SURE caps the total field at 120 runners across all three distances, and online registration closes at 23:59:59 the Wednesday of race week with no race-day registration offered. If you want in, plan to register well ahead rather than deciding the week of.
With no official vert figure published for the course, plan your pacing around exposure and cutoffs rather than a big elevation crux. The prairie and sandhills terrain will still slow you down more than the flat mileage suggests.
Both the 25K and 50K share a 10 hour cutoff, so treat early pace conservatively and bank time for the sandhill sections where footing gets softer and slower. A steady, repeatable effort beats an aggressive early pace you cannot sustain across open, exposed miles.
The 100K's 11pm cutoff, 16 hours after a 7am start, means most finishers will spend real time running after sunset. Practice night navigation and pacing on your own training runs, and build in a buffer against the cutoff rather than racing it down to the wire.
⏵ Free tools to plan your effort
With long, exposed stretches of open prairie and April weather in North Dakota that can swing from cold and windy to genuinely warm, your fueling and hydration plan needs real flexibility.
Aim for roughly 60 to 90 grams of carbohydrate per hour while moving, and sodium in the 300 to 700 mg per liter range, leaning toward the higher end if race day turns windy or warm across the exposed sandhills sections. Carry more fluid capacity than you think you need for the open stretches between aid.
⏵ Build your fueling plan
Get a carb, sodium, fluid, and caffeine plan per hour built for your weight and your chosen distance 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 training plan built around YOUR fitness and the point-to-point, exposed terrain of the Sheyenne National Grasslands. Summit Line reads your real training, builds the durability your chosen distance demands, and rehearses your fueling so race day is something you execute, not guess at.
END-SURE, short for the Extreme North Dakota Sandhills Ultra Run Experience, is a point-to-point trail ultra run by END Racing on the North Country Trail through the entire Sheyenne National Grasslands, about 45 minutes southwest of Fargo. It offers 25K, 50K, and 100K distances, all starting at 7am from Jorgen's Hollow Campground near McLeod, North Dakota.
The official race page lists the next edition for April 2027 but does not publish an exact day as of this writing. Check the official END-SURE page or the END Racing contact page for the confirmed date once it is announced, and register early since the field is capped at 120 runners across all distances.
The 25K has a 6pm cutoff (10 hours from the 7am start), the 50K has a 5pm cutoff (also 10 hours), and the 100K has an 11pm cutoff (16 hours). All three distances share the same 7am start time, so the longer the distance, the more of your day and evening you should plan to give it.
The Sheyenne National Grasslands is not mountain terrain, there is no big vertical crux here, but it is a genuine point-to-point trail ultra across open prairie and rolling sandhills with real exposure to wind and sun and little shade for long stretches. The 100K in particular is a long day and evening effort on foot with a 16 hour window, and the sandy, rolling terrain underfoot adds real fatigue that flat mileage numbers do not capture.
The 25K is a reasonable first-ultra distance with a generous 10 hour cutoff and straightforward point-to-point navigation on a marked national trail, which keeps the logistics manageable for a newer runner. The 50K shares the same cutoff window, so it demands more sustained pace but is not technically harder. The 100K, with its 16 hour cutoff, is better suited to someone who has already finished a shorter ultra and wants a genuine point-to-point challenge.
With cutoffs from 10 to 16 hours depending on distance, and exposed prairie terrain that can run hot or windy depending on the April weather, plan for roughly 60 to 90 grams of carbohydrate per hour while moving and sodium in the 300 to 700 mg per liter range, adjusted upward if the day turns warm or windy. Build your own numbers with the free ultra fueling calculator before race day.
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<a href="https://runsummitline.com/guides/end-sure">The END-SURE course guide</a><iframe src="https://runsummitline.com/embed/race/end-sure" style="width:100%;max-width:420px;height:180px;border:0;" loading="lazy" title="END-SURE course guide by Summit Line"></iframe>This guide is independent and for planning only. The date, cutoffs, and course details come from the official END Racing site and can change year to year, so confirm the current specifics before you register or run. The fueling and pacing advice is general and not medical advice.
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