⏵ Course guide · Ouachita Mountains marathon
Athens Big Fork Trail Marathon sends runners out and back across eight named Ouachita Mountain crossings on a horse postal trail more than a century old, since 1999 self-styled the toughest trail marathon in the South. I will walk you through the mountain-by-mountain course first, then give you a pacing and fueling plan built around its two hard cutoffs, plus free calculators to dial in your own numbers.
These facts come from the official race website. Check the current year details, cutoffs, and registration status before you commit. Race logistics change year to year.
The marathon starts and finishes at Big Fork Community Center, reaching the trail proper by road before turning around at mile 13.1 and running the same terrain home.
You open with about 2.5 miles on paved and gravel roads, Hwy 8, County Rd 83, and Forest Rd B15, to reach the Athens-Big Fork Northern Trailhead. From there you follow the trail’s white blazes over eight named mountains: Missouri, Hurricane Knob, McKinley, Brier Creek, Leader, Brush Heap, Brushy, and Big Tom, before popping out onto a gravel road and a half mile to the turnaround at Forest Rd B23F.
The Athens-Big Fork Trail predates the race by decades, originally a horse postal route through these mountains. Despite the permanent white blazes, the race adds spray chalk, flour, and orange cones at road intersections, and you will want your own sense of the route regardless, since eight mountain crossings leave plenty of room to lose focus on tired legs.
Runners who want the format without the full mileage can take the 17 Mile Blaylock Creek Fun Run, which shares the marathon’s road approach and first four mountain crossings before turning around at the aid station just across Blaylock Creek, skipping the second half of the climbing.
Two intermediate cutoffs, mile 8.5 by 10:30 AM and mile 22.4 by 3:42 PM, bracket the hardest terrain on the course, so your early pace matters more here than the overall marathon average suggests.
Reaching mile 8.5 by 10:30 AM, 2.5 hours after the 8:00 AM start, means averaging under 18 minutes per mile across terrain that already includes several mountain crossings. A grade-adjusted pace target for the climbs helps you judge honestly whether your effort on Missouri, Hurricane Knob, and McKinley is fast enough to bank the buffer you will want later.
Every mountain you cross outbound, you cross again on the way back, on legs that have already climbed roughly 7,000 feet. A race-time estimate built from real training on similarly steep, repeated terrain gives you a more honest target than assuming your outbound split simply doubles for the return.
⏵ Free tools to pace this course
This is a cupless race, so bring your own cup or handheld to every aid station, and plan your intake around a January morning in the Ouachita Mountains that can start cold and warm up through the afternoon.
Aim for roughly 60 to 90 grams of carbohydrate per hour given the sustained climbing, and take full advantage of the aid at Blaylock Creek and Little Missouri, including the famous Arkansas Crepes, since the stretches of trail between them and the turnaround are long and unsupported by comparison.
Sodium in the 300 to 700 mg per liter range covers most runners, and a January day here can start well below freezing at elevation before warming into the afternoon, so plan to adjust your intake as conditions shift across the roughly seven-plus hours before the final cutoff.
⏵ Build your fueling plan
Get a carb, sodium, fluid, and caffeine plan per hour built for your weight, your goal time, and a cold Ouachita Mountains morning 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 course's eight mountain crossings, and its two hard cutoffs. Summit Line reads your real training, builds a plan for repeated climbing, and rehearses your fueling so race day is something you execute, not guess at.
It bills itself as the "Toughest Trail Marathon in the South" for good reason: the out-and-back course crosses eight named mountains, Missouri, Hurricane Knob, McKinley, Brier Creek, Leader, Brush Heap, Brushy, and Big Tom, on the Athens-Big Fork Trail, a horse postal route more than a century old. The organizers quote about 7,000 feet of climbing on just the outbound half to the turnaround at mile 13.1, and you run essentially the same terrain back.
Marathon runners must reach the Blaylock Creek West Trailhead, mile 8.5 outbound, by 10:30 AM, and the Little Missouri Trailhead, mile 22.4 inbound, by 3:42 PM. Both are meaningful checkpoints given the eight mountain crossings between them, so respect the early cutoff rather than assuming the overall time budget covers a slow start.
This is a cupless race, so bring your own cup or handheld to the aid stations, which are stocked with typical ultra fare and the famous Arkansas Crepes at Blaylock Creek. Aim for roughly 60 to 90 grams of carbohydrate per hour given the climbing, and keep sodium in the 300 to 700 mg per liter range for a January day in the Ouachitas, which can swing from cold mornings to milder afternoons. Build your numbers with the free ultra fueling calculator before race day.
You start with about 2.5 miles on paved and gravel roads to reach the Athens-Big Fork Trail, then follow its white blazes over eight mountain crossings to a turnaround on Forest Rd B23F at mile 13.1, before running the same terrain back. The trail itself is a horse postal route dating back over a hundred years, and the race adds spray chalk, flour, and orange cones at road intersections on top of the permanent blazes.
The Fun Run only takes on half of the eight mountain crossings, turning around at the aid station just across Blaylock Creek instead of continuing to the full marathon turnaround at mile 13.1. It shares the same 8:00 AM start and road approach as the marathon, just with a shorter, less demanding turnaround point.
The race has historically run as a donation-only event with a 225-runner field limit and frequently fills, with a wait list that moves as registered runners drop in the weeks before race day. Starting with the 2027 race, the event is transitioning to a traditional registration fee while keeping proceeds directed to the Big Fork Community Center and the Ouachita Amateur Radio Association, which supports on-course safety.
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<a href="https://runsummitline.com/guides/athens-big-fork-trail-marathon">The Athens Big Fork Trail Marathon course guide</a><iframe src="https://runsummitline.com/embed/race/athens-big-fork-trail-marathon" style="width:100%;max-width:420px;height:180px;border:0;" loading="lazy" title="Athens Big Fork Trail Marathon course guide by Summit Line"></iframe>This guide is independent and for planning only. The course details, dates, cutoffs, and registration status 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.
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