⏵ Course guide · Montana trail ultra
Trail Rail Run runs point-to-point on historic railroad grades from Mullan, Idaho to St. Regis, Montana, crossing two century-old train trestles and one tunnel along the way. I will walk you through the course and its net downhill profile, then give you a pacing and fueling plan for the 50 Mile, 50K, 30K, 12K, or 5K. There are free calculators along the way to dial in your own numbers.
These facts come from the official Trail Rail Run site. Check the current year details before you commit. Race logistics can change year to year.
This is a point-to-point route, not a loop, following the old railroad grade from Mullan, Idaho all the way to St. Regis, Montana. The surface stays runnable throughout: 95% unpaved railroad ballast, dirt, and gravel.
The signature features of the course are two historic train trestles and one tunnel, carryovers from the route's life as an active rail line. They give the run a genuinely different character than a typical singletrack ultra, wide, graded, and built for a purpose other than foot traffic, which keeps footing predictable even as fatigue sets in late in the race.
You start at 3,278 ft in Mullan and finish at 2,635 ft in St. Regis, a net drop of 2,065 ft. That downhill bias is real, but you earn it: the course climbs to a 4,700 ft high point at Lookout Pass first, part of about 1,500 ft of total elevation gain across the route. Plan for genuine climbing in the early-to-middle miles before the net descent starts paying you back.
The event offers a 50 Mile, 50K, 30K, 12K, and 5K, so there is an entry point whether you want the full point-to-point ultra experience or a shorter taste of the same historic grade. A 50 Mile relay for teams of 2 to 7 runners and a hand cyclist category round out the field. The race has run since 2013, is organized by the St. Regis Community Center and Superior Ranger District, and is USATF sanctioned.
A net descent can tempt you into going out too hard on the early climbing before you have banked the fitness to hold it. Respect the 4,700 ft high point at Lookout Pass before you start banking on the downhill miles that follow.
The climb to Lookout Pass comes before the net downhill kicks in, so treat those early miles like any other ultra climb: controlled effort, not pace-chasing. Runners who burn matches getting to the high point tend to give back more than they saved once the legs are pounding downhill and unpaved railroad ballast late in a 50 Mile effort.
With a 14 hour cutoff for the 50 Mile (9:00 PM MDT), work backward from that number using a realistic average pace across 10 aid stations, factoring in more time on the climb to Lookout Pass and faster splits once you are descending toward St. Regis.
⏵ Free tools to plan your effort
With 10 aid stations along the point-to-point route, you have regular chances to refuel, but for a 14 hour effort you still need a per-hour plan of your own rather than relying on aid alone.
A general starting point for a race in this length range is roughly 60 to 90 grams of carbohydrate per hour while moving and sodium in the 300 to 700 mg per liter range, adjusted for a June day in the Bitterroots. Use the aid stations to top off rather than as your only fueling source, and carry what you need between them.
Because the course mixes real climbing to Lookout Pass with a long net descent on railroad ballast and gravel, rehearse eating and drinking on similar terrain in training, not just on flat roads. Your gut tolerance on a sustained downhill grade can differ from how it handles a climb.
⏵ Build your fueling plan
Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and the course profile 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 climb to Lookout Pass followed by a long downhill grind into St. Regis. Summit Line reads your real training, builds the durability this course demands, and rehearses your fueling so race day is something you execute, not guess at.
It is a point-to-point route on historic railroad grades running from Mullan, Idaho to St. Regis, Montana. The surface is 95% unpaved, a mix of railroad ballast, dirt, and gravel, and the highlight is two historic train trestles plus one tunnel along the way. The course climbs to a high point of 4,700 ft at Lookout Pass before dropping to a 2,635 ft finish in St. Regis, so despite roughly 1,500 ft of total climbing, the net effect over the full 50 Mile is a 2,065 ft descent.
The net downhill profile helps, but do not mistake this for an easy 50. You still climb to a 4,700 ft high point at Lookout Pass, and the unpaved railroad ballast and gravel surface asks more of your legs over 50 miles than pavement would. The 14 hour cutoff is generous for a well-prepared ultra runner, but the point-to-point logistics and the length of time on your feet still make it a genuine ultramarathon effort.
The 50 Mile distance has a 14 hour cutoff, meaning finishers need to reach St. Regis by 9:00 PM MDT. The official site did not publish separate cutoffs for the shorter 50K, 30K, 12K, and 5K distances at the time this guide was written, so check the current-year athlete information for those before you commit to a pace plan.
The net downhill course and a 14 hour cutoff for the 50 Mile make it a reasonable target for a first ultra if you already have some trail experience, and the 50K option is a solid stepping stone if 50 miles feels like too much on a first try. The unpaved railroad-grade surface is runnable rather than technical, which keeps the terrain forgiving even as the distance adds up.
There are 10 aid stations spread across the course, which for a point-to-point route through Mullan, Lookout Pass, and down into St. Regis gives you regular, predictable spots to refuel and check in rather than long unsupported stretches.
Five individual distances: a 50 Mile, a 50K, a 30K, a 12K, and a 5K. There is also a 50 Mile relay for teams of 2 to 7 runners and a hand cyclist category for the 50 Mile, so the event covers a wide range of ability levels and ways to take part on the same historic route.
Link this guide
Race directors and clubs: link or embed this guide anywhere. It stays current.
<a href="https://runsummitline.com/guides/trail-rail-run">The Trail Rail Run course guide</a><iframe src="https://runsummitline.com/embed/race/trail-rail-run" style="width:100%;max-width:420px;height:180px;border:0;" loading="lazy" title="Trail Rail Run course guide by Summit Line"></iframe>This guide is independent and for planning only. The course, cutoffs, and logistics 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.