⏵ Course guide · North Menan Butte, Idaho
The Spitfire Ultra runs a genuinely different course than most Idaho trail races: rugged volcanic terrain on North Menan Butte, with dirt, mud, sand, and slick rock, plus views of the Tetons and the Snake River. I will walk you through the course and cutoffs first, then give you a pacing and fueling plan for the 55K, 30K, 12K, or 5K. There are free calculators along the way to dial in your own numbers.
These facts come from the official Spitfire Ultra race site and its FAQ page. Check the current year details before you commit.
All four distances race on North Menan Butte itself, a real extinct volcano, so the footing shifts constantly between dirt, mud, sand, and slick rock rather than settling into one predictable surface.
The 5K (Bad Ash), 12K (Fab Challenge), 30K (Epic Challenge), and 55K (The FAT 55K Ultra) all use the butte, with staggered starts from 6:00 AM (55K) through 10:30 AM (5K). Expect real climbing and descending mixed with flatter stretches, and sand and slick rock that slow your pace more than a flat mileage number would suggest.
The race enforces no shortcutting on switchbacks, since doing so risks the permit that lets the event use the butte at all. South Butte sections cross private land and are only accessible on race day, so this is genuinely a once-a-year chance to run that part of the course.
Bring your own cup or hydration system. The 30K and 55K require you to check in at every aid station, a rule the race enforces for safety, and runners pulled for missing a cutoff have to remove their bib and stop as a registered participant.
No elevation gain figure is published, so lean on the terrain description and the 55K's firm 3:00 PM cutoff to set your pace rather than a specific vert target.
Volcanic sand and slick rock slow a runner down more than a comparable climb on packed singletrack, so do not assume your usual pace-per-mile from a groomed course will hold here. Build a conservative early pace on the 55K so the 9-hour window from 6:00 AM to 3:00 PM stays comfortable rather than tight.
⏵ Free tools to plan your effort
Because this is a cupless race with mandatory aid check-ins, your hydration plan has to account for carrying your own vessel, not just your own calories.
Aim for roughly 60 to 90 grams of carbohydrate per hour on the 55K and sodium in the 300 to 700 mg per liter range, adjusted for a mid-April Idaho day that can still run cool early and warm up by afternoon. Since sand and slick rock will likely slow your splits versus a groomed course, plan your fueling schedule around time on feet rather than an optimistic pace assumption.
⏵ Build your fueling plan
Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and a mid-April Idaho 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 training plan built around YOUR fitness and the kind of technical, sand-and-rock footing this course demands. Summit Line reads your real training, builds the durability your distance asks for, and rehearses your fueling so race day is something you execute, not guess at.
The Spitfire Ultra runs every 3rd Saturday of April, and the next confirmed date on the official race site is Saturday, April 17, 2027. Registration and further details are handled through the race site and UltraSignup, so confirm current entry status there before you commit.
The course covers rugged volcanic terrain on North Menan Butte, a genuine mix of dirt, mud, sand, and slick rock with real climbing and descending, not a groomed singletrack day. Neither the race site nor its FAQ page publishes a total elevation gain figure, so treat the terrain description itself as your best guide: this is a technical, footing-dependent ultra rather than a fast, runnable one, and the 55K's 6:00 AM to 3:00 PM cutoff gives you 9 hours to work with.
The 55K has a firm finish cutoff: "everyone has to be finished by 3 pm," which is 9 hours from its 6:00 AM start. The race also requires mandatory check-in at every aid station on the 30K and 55K, and runners pulled for missing a cutoff are removed from the field and asked to hand back their bib, so treat the aid-station check-ins as real checkpoints, not optional stops.
Yes. Bring your own cup or hydration system for every aid station, and consider bringing your own plate and utensils for the post-race potato bar as well, since the race asks runners to help reduce waste there too.
The volcanic terrain, sand, mud, slick rock, and real elevation change, makes this a more technical first ultra than a groomed forest course, so it rewards runners who have already spent time on uneven footing. That said, the shorter 12K and 30K options let you sample the same volcano terrain at a lower commitment first, and the race's multiple distances and family-friendly post-race spread make it a welcoming event to build up through.
With no published elevation figure and technical, sandy footing that slows most runners down, build your fueling plan around your realistic time on feet rather than a fast-course assumption. Aim for roughly 60 to 90 grams of carbohydrate per hour on the 55K and sodium in the 300 to 700 mg per liter range, and remember this is a cupless race, so your hydration plan has to account for carrying or using your own vessel at every stop. Use the free ultra fueling calculator to build your own numbers.
Link this guide
Race directors and clubs: link or embed this guide anywhere. It stays current.
<a href="https://runsummitline.com/guides/the-spitfire-ultra">The The Spitfire Ultra course guide</a><iframe src="https://runsummitline.com/embed/race/the-spitfire-ultra" style="width:100%;max-width:420px;height:180px;border:0;" loading="lazy" title="The Spitfire Ultra course guide by Summit Line"></iframe>This guide is independent and for planning only. The course details, dates, and entry rules 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.
The timeline
Get the week-by-week countdown for this race: when to build, when to peak, when to taper.
One email with the timeline, plus training notes for this race. Unsubscribe any time.